feat(tui): Phase 2 Issue List + MR List screens

Implement state, action, and view layers for both list screens:
- Issue List: keyset pagination, snapshot fence, filter DSL, label aggregation
- MR List: mirrors Issue pattern with draft/reviewer/target branch filters
- Migration 027: covering indexes for TUI list screen queries
- Updated Msg types to use typed Page structs instead of raw Vec<Row>
- 303 tests passing, clippy clean

Beads: bd-3ei1, bd-2kr0, bd-3pm2

crates/lore-tui/src/commands/defs.rs

@@ -0,0 +1,180 @@
+//! Command definitions — types for keybindings, screen filtering, and command metadata.
+
+use ftui::{KeyCode, Modifiers};
+
+use crate::message::Screen;
+
+// ---------------------------------------------------------------------------
+// Key formatting
+// ---------------------------------------------------------------------------
+
+/// Format a key code + modifiers as a human-readable string.
+pub(crate) fn format_key(code: KeyCode, modifiers: Modifiers) -> String {
+    let mut parts = Vec::new();
+    if modifiers.contains(Modifiers::CTRL) {
+        parts.push("Ctrl");
+    }
+    if modifiers.contains(Modifiers::ALT) {
+        parts.push("Alt");
+    }
+    if modifiers.contains(Modifiers::SHIFT) {
+        parts.push("Shift");
+    }
+    let key_name = match code {
+        KeyCode::Char(c) => c.to_string(),
+        KeyCode::Enter => "Enter".to_string(),
+        KeyCode::Escape => "Esc".to_string(),
+        KeyCode::Tab => "Tab".to_string(),
+        KeyCode::Backspace => "Backspace".to_string(),
+        KeyCode::Delete => "Del".to_string(),
+        KeyCode::Up => "Up".to_string(),
+        KeyCode::Down => "Down".to_string(),
+        KeyCode::Left => "Left".to_string(),
+        KeyCode::Right => "Right".to_string(),
+        KeyCode::Home => "Home".to_string(),
+        KeyCode::End => "End".to_string(),
+        KeyCode::PageUp => "PgUp".to_string(),
+        KeyCode::PageDown => "PgDn".to_string(),
+        KeyCode::F(n) => format!("F{n}"),
+        _ => "?".to_string(),
+    };
+    parts.push(&key_name);
+    // We need to own the joined string.
+    let joined: String = parts.join("+");
+    joined
+}
+
+// ---------------------------------------------------------------------------
+// KeyCombo
+// ---------------------------------------------------------------------------
+
+/// A keybinding: either a single key or a two-key sequence.
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum KeyCombo {
+    /// Single key press (e.g., `q`, `Esc`, `Ctrl+P`).
+    Single { code: KeyCode, modifiers: Modifiers },
+    /// Two-key sequence (e.g., `g` then `i` for go-to-issues).
+    Sequence {
+        first_code: KeyCode,
+        first_modifiers: Modifiers,
+        second_code: KeyCode,
+        second_modifiers: Modifiers,
+    },
+}
+
+impl KeyCombo {
+    /// Convenience: single key with no modifiers.
+    #[must_use]
+    pub const fn key(code: KeyCode) -> Self {
+        Self::Single {
+            code,
+            modifiers: Modifiers::NONE,
+        }
+    }
+
+    /// Convenience: single key with Ctrl modifier.
+    #[must_use]
+    pub const fn ctrl(code: KeyCode) -> Self {
+        Self::Single {
+            code,
+            modifiers: Modifiers::CTRL,
+        }
+    }
+
+    /// Convenience: g-prefix sequence (g + char).
+    #[must_use]
+    pub const fn g_then(c: char) -> Self {
+        Self::Sequence {
+            first_code: KeyCode::Char('g'),
+            first_modifiers: Modifiers::NONE,
+            second_code: KeyCode::Char(c),
+            second_modifiers: Modifiers::NONE,
+        }
+    }
+
+    /// Human-readable display string for this key combo.
+    #[must_use]
+    pub fn display(&self) -> String {
+        match self {
+            Self::Single { code, modifiers } => format_key(*code, *modifiers),
+            Self::Sequence {
+                first_code,
+                first_modifiers,
+                second_code,
+                second_modifiers,
+            } => {
+                let first = format_key(*first_code, *first_modifiers);
+                let second = format_key(*second_code, *second_modifiers);
+                format!("{first} {second}")
+            }
+        }
+    }
+
+    /// Whether this combo starts with the given key.
+    #[must_use]
+    pub fn starts_with(&self, code: &KeyCode, modifiers: &Modifiers) -> bool {
+        match self {
+            Self::Single {
+                code: c,
+                modifiers: m,
+            } => c == code && m == modifiers,
+            Self::Sequence {
+                first_code,
+                first_modifiers,
+                ..
+            } => first_code == code && first_modifiers == modifiers,
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// ScreenFilter
+// ---------------------------------------------------------------------------
+
+/// Specifies which screens a command is available on.
+#[derive(Debug, Clone)]
+pub enum ScreenFilter {
+    /// Available on all screens.
+    Global,
+    /// Available only on specific screens.
+    Only(Vec<Screen>),
+}
+
+impl ScreenFilter {
+    /// Whether the command is available on the given screen.
+    #[must_use]
+    pub fn matches(&self, screen: &Screen) -> bool {
+        match self {
+            Self::Global => true,
+            Self::Only(screens) => screens.contains(screen),
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// CommandDef
+// ---------------------------------------------------------------------------
+
+/// Unique command identifier.
+pub type CommandId = &'static str;
+
+/// A registered command with its keybinding, help text, and scope.
+#[derive(Debug, Clone)]
+pub struct CommandDef {
+    /// Unique identifier (e.g., "quit", "go_issues").
+    pub id: CommandId,
+    /// Human-readable label for palette and help overlay.
+    pub label: &'static str,
+    /// Keybinding (if any).
+    pub keybinding: Option<KeyCombo>,
+    /// Equivalent `lore` CLI command (for "Show CLI equivalent" feature).
+    pub cli_equivalent: Option<&'static str>,
+    /// Description for help overlay.
+    pub help_text: &'static str,
+    /// Short hint for status bar (e.g., "q:quit").
+    pub status_hint: &'static str,
+    /// Which screens this command is available on.
+    pub available_in: ScreenFilter,
+    /// Whether this command works in Text input mode.
+    pub available_in_text_mode: bool,
+}

crates/lore-tui/src/commands/mod.rs

@@ -0,0 +1,227 @@
+#![allow(dead_code)] // Phase 1: consumed by LoreApp in bd-6pmy
+
+//! Command registry — single source of truth for all TUI actions.
+//!
+//! Every keybinding, palette entry, help text, CLI equivalent, and
+//! status hint is generated from [`CommandRegistry`]. No hardcoded
+//! duplicate maps exist in view/state modules.
+//!
+//! Supports single-key and two-key sequences (g-prefix vim bindings).
+
+mod defs;
+mod registry;
+
+// Re-export public API — preserves `crate::commands::{CommandRegistry, build_registry, ...}`.
+pub use defs::{CommandDef, CommandId, KeyCombo, ScreenFilter};
+pub use registry::{CommandRegistry, build_registry};
+
+// ---------------------------------------------------------------------------
+// Tests
+// ---------------------------------------------------------------------------
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use chrono::Utc;
+    use ftui::{KeyCode, Modifiers};
+
+    use crate::message::{InputMode, Screen};
+
+    #[test]
+    fn test_registry_builds_successfully() {
+        let reg = build_registry();
+        assert!(!reg.is_empty());
+        assert!(reg.len() >= 15);
+    }
+
+    #[test]
+    fn test_registry_lookup_quit() {
+        let reg = build_registry();
+        let cmd = reg.lookup_key(
+            &KeyCode::Char('q'),
+            &Modifiers::NONE,
+            &Screen::Dashboard,
+            &InputMode::Normal,
+        );
+        assert!(cmd.is_some());
+        assert_eq!(cmd.unwrap().id, "quit");
+    }
+
+    #[test]
+    fn test_registry_lookup_quit_blocked_in_text_mode() {
+        let reg = build_registry();
+        let cmd = reg.lookup_key(
+            &KeyCode::Char('q'),
+            &Modifiers::NONE,
+            &Screen::Dashboard,
+            &InputMode::Text,
+        );
+        assert!(cmd.is_none());
+    }
+
+    #[test]
+    fn test_registry_esc_works_in_text_mode() {
+        let reg = build_registry();
+        let cmd = reg.lookup_key(
+            &KeyCode::Escape,
+            &Modifiers::NONE,
+            &Screen::IssueList,
+            &InputMode::Text,
+        );
+        assert!(cmd.is_some());
+        assert_eq!(cmd.unwrap().id, "go_back");
+    }
+
+    #[test]
+    fn test_registry_ctrl_p_works_in_text_mode() {
+        let reg = build_registry();
+        let cmd = reg.lookup_key(
+            &KeyCode::Char('p'),
+            &Modifiers::CTRL,
+            &Screen::Search,
+            &InputMode::Text,
+        );
+        assert!(cmd.is_some());
+        assert_eq!(cmd.unwrap().id, "command_palette");
+    }
+
+    #[test]
+    fn test_g_is_sequence_starter() {
+        let reg = build_registry();
+        assert!(reg.is_sequence_starter(&KeyCode::Char('g'), &Modifiers::NONE));
+        assert!(!reg.is_sequence_starter(&KeyCode::Char('x'), &Modifiers::NONE));
+    }
+
+    #[test]
+    fn test_complete_sequence_gi() {
+        let reg = build_registry();
+        let cmd = reg.complete_sequence(
+            &KeyCode::Char('g'),
+            &Modifiers::NONE,
+            &KeyCode::Char('i'),
+            &Modifiers::NONE,
+            &Screen::Dashboard,
+        );
+        assert!(cmd.is_some());
+        assert_eq!(cmd.unwrap().id, "go_issues");
+    }
+
+    #[test]
+    fn test_complete_sequence_invalid_second_key() {
+        let reg = build_registry();
+        let cmd = reg.complete_sequence(
+            &KeyCode::Char('g'),
+            &Modifiers::NONE,
+            &KeyCode::Char('x'),
+            &Modifiers::NONE,
+            &Screen::Dashboard,
+        );
+        assert!(cmd.is_none());
+    }
+
+    #[test]
+    fn test_screen_specific_command() {
+        let reg = build_registry();
+        // 'j' (move_down) should work on IssueList
+        let cmd = reg.lookup_key(
+            &KeyCode::Char('j'),
+            &Modifiers::NONE,
+            &Screen::IssueList,
+            &InputMode::Normal,
+        );
+        assert!(cmd.is_some());
+        assert_eq!(cmd.unwrap().id, "move_down");
+
+        // 'j' should NOT match on Dashboard (move_down is list-only).
+        let cmd = reg.lookup_key(
+            &KeyCode::Char('j'),
+            &Modifiers::NONE,
+            &Screen::Dashboard,
+            &InputMode::Normal,
+        );
+        assert!(cmd.is_none());
+    }
+
+    #[test]
+    fn test_palette_entries_sorted_by_label() {
+        let reg = build_registry();
+        let entries = reg.palette_entries(&Screen::Dashboard);
+        let labels: Vec<&str> = entries.iter().map(|c| c.label).collect();
+        let mut sorted = labels.clone();
+        sorted.sort();
+        assert_eq!(labels, sorted);
+    }
+
+    #[test]
+    fn test_help_entries_only_include_keybindings() {
+        let reg = build_registry();
+        let entries = reg.help_entries(&Screen::Dashboard);
+        for entry in &entries {
+            assert!(
+                entry.keybinding.is_some(),
+                "help entry without keybinding: {}",
+                entry.id
+            );
+        }
+    }
+
+    #[test]
+    fn test_status_hints_non_empty() {
+        let reg = build_registry();
+        let hints = reg.status_hints(&Screen::Dashboard);
+        assert!(!hints.is_empty());
+        // All returned hints should be non-empty strings.
+        for hint in &hints {
+            assert!(!hint.is_empty());
+        }
+    }
+
+    #[test]
+    fn test_cli_equivalents_populated() {
+        let reg = build_registry();
+        let with_cli: Vec<&CommandDef> = reg
+            .commands
+            .iter()
+            .filter(|c| c.cli_equivalent.is_some())
+            .collect();
+        assert!(
+            with_cli.len() >= 5,
+            "expected at least 5 commands with cli_equivalent, got {}",
+            with_cli.len()
+        );
+    }
+
+    #[test]
+    fn test_go_prefix_timeout_detection() {
+        let reg = build_registry();
+        // Simulate GoPrefix mode entering: 'g' detected as sequence starter.
+        assert!(reg.is_sequence_starter(&KeyCode::Char('g'), &Modifiers::NONE));
+
+        // Simulate InputMode::GoPrefix with timeout check.
+        let started = Utc::now();
+        let mode = InputMode::GoPrefix {
+            started_at: started,
+        };
+        // In GoPrefix mode, normal lookup should still work for non-sequence keys.
+        let cmd = reg.lookup_key(
+            &KeyCode::Char('q'),
+            &Modifiers::NONE,
+            &Screen::Dashboard,
+            &mode,
+        );
+        assert!(cmd.is_some());
+        assert_eq!(cmd.unwrap().id, "quit");
+    }
+
+    #[test]
+    fn test_all_commands_have_nonempty_help() {
+        let reg = build_registry();
+        for cmd in &reg.commands {
+            assert!(
+                !cmd.help_text.is_empty(),
+                "command {} has empty help_text",
+                cmd.id
+            );
+        }
+    }
+}

crates/lore-tui/src/commands/registry.rs

@@ -0,0 +1,418 @@
+//! Command registry — lookup, indexing, and the canonical command list.
+
+use std::collections::HashMap;
+
+use ftui::{KeyCode, Modifiers};
+
+use crate::message::{InputMode, Screen};
+
+use super::defs::{CommandDef, KeyCombo, ScreenFilter};
+
+// ---------------------------------------------------------------------------
+// CommandRegistry
+// ---------------------------------------------------------------------------
+
+/// Single source of truth for all TUI commands.
+///
+/// Built once at startup via [`build_registry`]. Provides O(1) lookup
+/// by keybinding and per-screen filtering.
+pub struct CommandRegistry {
+    pub(crate) commands: Vec<CommandDef>,
+    /// Single-key -> command IDs that start with this key.
+    by_single_key: HashMap<(KeyCode, Modifiers), Vec<usize>>,
+    /// Full sequence -> command index (for two-key combos).
+    by_sequence: HashMap<KeyCombo, usize>,
+}
+
+impl CommandRegistry {
+    /// Look up a command by a single key press on a given screen and input mode.
+    ///
+    /// Returns `None` if no matching command is found. For sequence starters
+    /// (like 'g'), returns `None` — use [`is_sequence_starter`] to detect
+    /// that case.
+    #[must_use]
+    pub fn lookup_key(
+        &self,
+        code: &KeyCode,
+        modifiers: &Modifiers,
+        screen: &Screen,
+        mode: &InputMode,
+    ) -> Option<&CommandDef> {
+        let is_text = matches!(mode, InputMode::Text);
+        let key = (*code, *modifiers);
+
+        let indices = self.by_single_key.get(&key)?;
+        for &idx in indices {
+            let cmd = &self.commands[idx];
+            if !cmd.available_in.matches(screen) {
+                continue;
+            }
+            if is_text && !cmd.available_in_text_mode {
+                continue;
+            }
+            // Only match Single combos here, not sequence starters.
+            if let Some(KeyCombo::Single { .. }) = &cmd.keybinding {
+                return Some(cmd);
+            }
+        }
+        None
+    }
+
+    /// Complete a two-key sequence.
+    ///
+    /// Called after the first key of a sequence is detected (e.g., after 'g').
+    #[must_use]
+    pub fn complete_sequence(
+        &self,
+        first_code: &KeyCode,
+        first_modifiers: &Modifiers,
+        second_code: &KeyCode,
+        second_modifiers: &Modifiers,
+        screen: &Screen,
+    ) -> Option<&CommandDef> {
+        let combo = KeyCombo::Sequence {
+            first_code: *first_code,
+            first_modifiers: *first_modifiers,
+            second_code: *second_code,
+            second_modifiers: *second_modifiers,
+        };
+        let &idx = self.by_sequence.get(&combo)?;
+        let cmd = &self.commands[idx];
+        if cmd.available_in.matches(screen) {
+            Some(cmd)
+        } else {
+            None
+        }
+    }
+
+    /// Whether a key starts a multi-key sequence (e.g., 'g').
+    #[must_use]
+    pub fn is_sequence_starter(&self, code: &KeyCode, modifiers: &Modifiers) -> bool {
+        self.by_sequence
+            .keys()
+            .any(|combo| combo.starts_with(code, modifiers))
+    }
+
+    /// Commands available for the command palette on a given screen.
+    ///
+    /// Returned sorted by label.
+    #[must_use]
+    pub fn palette_entries(&self, screen: &Screen) -> Vec<&CommandDef> {
+        let mut entries: Vec<&CommandDef> = self
+            .commands
+            .iter()
+            .filter(|c| c.available_in.matches(screen))
+            .collect();
+        entries.sort_by_key(|c| c.label);
+        entries
+    }
+
+    /// Commands for the help overlay on a given screen.
+    #[must_use]
+    pub fn help_entries(&self, screen: &Screen) -> Vec<&CommandDef> {
+        self.commands
+            .iter()
+            .filter(|c| c.available_in.matches(screen))
+            .filter(|c| c.keybinding.is_some())
+            .collect()
+    }
+
+    /// Status bar hints for the current screen.
+    #[must_use]
+    pub fn status_hints(&self, screen: &Screen) -> Vec<&str> {
+        self.commands
+            .iter()
+            .filter(|c| c.available_in.matches(screen))
+            .filter(|c| !c.status_hint.is_empty())
+            .map(|c| c.status_hint)
+            .collect()
+    }
+
+    /// Total number of registered commands.
+    #[must_use]
+    pub fn len(&self) -> usize {
+        self.commands.len()
+    }
+
+    /// Whether the registry has no commands.
+    #[must_use]
+    pub fn is_empty(&self) -> bool {
+        self.commands.is_empty()
+    }
+}
+
+// ---------------------------------------------------------------------------
+// build_registry
+// ---------------------------------------------------------------------------
+
+/// Build the command registry with all TUI commands.
+///
+/// This is the single source of truth — every keybinding, help text,
+/// and palette entry originates here.
+#[must_use]
+pub fn build_registry() -> CommandRegistry {
+    let commands = vec![
+        // --- Global commands ---
+        CommandDef {
+            id: "quit",
+            label: "Quit",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('q'))),
+            cli_equivalent: None,
+            help_text: "Exit the TUI",
+            status_hint: "q:quit",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_back",
+            label: "Go Back",
+            keybinding: Some(KeyCombo::key(KeyCode::Escape)),
+            cli_equivalent: None,
+            help_text: "Go back to previous screen",
+            status_hint: "esc:back",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: true,
+        },
+        CommandDef {
+            id: "show_help",
+            label: "Help",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('?'))),
+            cli_equivalent: None,
+            help_text: "Show keybinding help overlay",
+            status_hint: "?:help",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "command_palette",
+            label: "Command Palette",
+            keybinding: Some(KeyCombo::ctrl(KeyCode::Char('p'))),
+            cli_equivalent: None,
+            help_text: "Open command palette",
+            status_hint: "C-p:palette",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: true,
+        },
+        CommandDef {
+            id: "open_in_browser",
+            label: "Open in Browser",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('o'))),
+            cli_equivalent: None,
+            help_text: "Open current entity in browser",
+            status_hint: "o:browser",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "show_cli",
+            label: "Show CLI Equivalent",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('!'))),
+            cli_equivalent: None,
+            help_text: "Show equivalent lore CLI command",
+            status_hint: "",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        // --- Navigation: g-prefix sequences ---
+        CommandDef {
+            id: "go_home",
+            label: "Go to Dashboard",
+            keybinding: Some(KeyCombo::g_then('h')),
+            cli_equivalent: None,
+            help_text: "Jump to dashboard",
+            status_hint: "gh:home",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_issues",
+            label: "Go to Issues",
+            keybinding: Some(KeyCombo::g_then('i')),
+            cli_equivalent: Some("lore issues"),
+            help_text: "Jump to issue list",
+            status_hint: "gi:issues",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_mrs",
+            label: "Go to Merge Requests",
+            keybinding: Some(KeyCombo::g_then('m')),
+            cli_equivalent: Some("lore mrs"),
+            help_text: "Jump to MR list",
+            status_hint: "gm:mrs",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_search",
+            label: "Go to Search",
+            keybinding: Some(KeyCombo::g_then('/')),
+            cli_equivalent: Some("lore search"),
+            help_text: "Jump to search",
+            status_hint: "g/:search",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_timeline",
+            label: "Go to Timeline",
+            keybinding: Some(KeyCombo::g_then('t')),
+            cli_equivalent: Some("lore timeline"),
+            help_text: "Jump to timeline",
+            status_hint: "gt:timeline",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_who",
+            label: "Go to Who",
+            keybinding: Some(KeyCombo::g_then('w')),
+            cli_equivalent: Some("lore who"),
+            help_text: "Jump to people intelligence",
+            status_hint: "gw:who",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "go_sync",
+            label: "Go to Sync",
+            keybinding: Some(KeyCombo::g_then('s')),
+            cli_equivalent: Some("lore sync"),
+            help_text: "Jump to sync status",
+            status_hint: "gs:sync",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        // --- Vim-style jump list ---
+        CommandDef {
+            id: "jump_back",
+            label: "Jump Back",
+            keybinding: Some(KeyCombo::ctrl(KeyCode::Char('o'))),
+            cli_equivalent: None,
+            help_text: "Jump backward through visited detail views",
+            status_hint: "C-o:jump back",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "jump_forward",
+            label: "Jump Forward",
+            keybinding: Some(KeyCombo::ctrl(KeyCode::Char('i'))),
+            cli_equivalent: None,
+            help_text: "Jump forward through visited detail views",
+            status_hint: "",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+        // --- List navigation ---
+        CommandDef {
+            id: "move_down",
+            label: "Move Down",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('j'))),
+            cli_equivalent: None,
+            help_text: "Move cursor down",
+            status_hint: "j:down",
+            available_in: ScreenFilter::Only(vec![
+                Screen::IssueList,
+                Screen::MrList,
+                Screen::Search,
+                Screen::Timeline,
+            ]),
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "move_up",
+            label: "Move Up",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('k'))),
+            cli_equivalent: None,
+            help_text: "Move cursor up",
+            status_hint: "k:up",
+            available_in: ScreenFilter::Only(vec![
+                Screen::IssueList,
+                Screen::MrList,
+                Screen::Search,
+                Screen::Timeline,
+            ]),
+            available_in_text_mode: false,
+        },
+        CommandDef {
+            id: "select_item",
+            label: "Select",
+            keybinding: Some(KeyCombo::key(KeyCode::Enter)),
+            cli_equivalent: None,
+            help_text: "Open selected item",
+            status_hint: "enter:open",
+            available_in: ScreenFilter::Only(vec![
+                Screen::IssueList,
+                Screen::MrList,
+                Screen::Search,
+            ]),
+            available_in_text_mode: false,
+        },
+        // --- Filter ---
+        CommandDef {
+            id: "focus_filter",
+            label: "Filter",
+            keybinding: Some(KeyCombo::key(KeyCode::Char('/'))),
+            cli_equivalent: None,
+            help_text: "Focus the filter input",
+            status_hint: "/:filter",
+            available_in: ScreenFilter::Only(vec![Screen::IssueList, Screen::MrList]),
+            available_in_text_mode: false,
+        },
+        // --- Scroll ---
+        CommandDef {
+            id: "scroll_to_top",
+            label: "Scroll to Top",
+            keybinding: Some(KeyCombo::g_then('g')),
+            cli_equivalent: None,
+            help_text: "Scroll to the top of the current view",
+            status_hint: "",
+            available_in: ScreenFilter::Global,
+            available_in_text_mode: false,
+        },
+    ];
+
+    build_from_defs(commands)
+}
+
+/// Build index maps from a list of command definitions.
+fn build_from_defs(commands: Vec<CommandDef>) -> CommandRegistry {
+    let mut by_single_key: HashMap<(KeyCode, Modifiers), Vec<usize>> = HashMap::new();
+    let mut by_sequence: HashMap<KeyCombo, usize> = HashMap::new();
+
+    for (idx, cmd) in commands.iter().enumerate() {
+        if let Some(combo) = &cmd.keybinding {
+            match combo {
+                KeyCombo::Single { code, modifiers } => {
+                    by_single_key
+                        .entry((*code, *modifiers))
+                        .or_default()
+                        .push(idx);
+                }
+                KeyCombo::Sequence { .. } => {
+                    by_sequence.insert(combo.clone(), idx);
+                    // Also index the first key so is_sequence_starter works via by_single_key.
+                    if let KeyCombo::Sequence {
+                        first_code,
+                        first_modifiers,
+                        ..
+                    } = combo
+                    {
+                        by_single_key
+                            .entry((*first_code, *first_modifiers))
+                            .or_default()
+                            .push(idx);
+                    }
+                }
+            }
+        }
+    }
+
+    CommandRegistry {
+        commands,
+        by_single_key,
+        by_sequence,
+    }
+}