refactor(sync): overhaul progress display with stage spinners and summaries

Phase 2 of the UX overhaul. Replaces the old numbered-stage progress
system (1/4, 2/4...) and manual indicatif ProgressBar/ProgressStyle
setup with the new centralized progress helpers.

Sync command changes (src/cli/commands/sync.rs):
- Replace stage_spinner(n, total, msg) with stage_spinner_v2(icon, label, status)
  removing the rigid numbered-stage counter in favor of named stages
- Replace manual ProgressBar::new + ProgressStyle::default_bar for docs
  and embed sub-progress with nested_progress(label, len, robot_mode)
- Add finish_stage() calls that display a completion summary with
  elapsed time, e.g. "Issues  42 issues from 3 projects  1.2s"
- Each stage (Issues, MRs, Docs, Embed) now reports what it did on
  completion rather than just clearing the spinner silently
- Embed failure path uses Icons::warning() instead of inline Theme
  formatting, keeping error display consistent with success path
- Remove indicatif direct dependency from sync.rs (now handled by
  progress module)

Main entry point changes (src/main.rs):
- Add GlyphMode detection: auto-detect Unicode/Nerd Font support or
  fall back to ASCII based on --icons flag, --color=never, NO_COLOR,
  or robot mode
- Update all LoreRenderer::init() calls to pass GlyphMode alongside
  ColorMode for icon-aware rendering throughout the CLI
- Overhaul handle_error() formatting: use Icons::error() glyph,
  bold error text, arrow prefixed action suggestions, and breathing
  room with blank lines for scannability
- Migrate handle_embed() progress bar from manual ProgressBar +
  ProgressStyle to nested_progress() helper, matching sync command

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/main.rs

@@ -25,7 +25,7 @@ use lore::cli::commands::{
     run_list_issues, run_list_mrs, run_search, run_show_issue, run_show_mr, run_stats, run_sync,
     run_sync_status, run_timeline, run_who,
 };
-use lore::cli::render::{ColorMode, LoreRenderer, Theme};
+use lore::cli::render::{ColorMode, GlyphMode, Icons, LoreRenderer, Theme};
 use lore::cli::robot::{RobotMeta, strip_schemas};
 use lore::cli::{
     Cli, Commands, CountArgs, EmbedArgs, GenerateDocsArgs, IngestArgs, IssuesArgs, MrsArgs,
@@ -145,24 +145,29 @@ async fn main() {
     }
 
     // I1: Respect NO_COLOR convention (https://no-color.org/)
+    let force_ascii = robot_mode
+        || cli.color == "never"
+        || std::env::var("NO_COLOR").is_ok_and(|v| !v.is_empty());
+    let glyphs = GlyphMode::detect(cli.icons.as_deref(), force_ascii);
+
     if std::env::var("NO_COLOR").is_ok_and(|v| !v.is_empty()) {
-        LoreRenderer::init(ColorMode::Never);
+        LoreRenderer::init(ColorMode::Never, glyphs);
         console::set_colors_enabled(false);
     } else {
         match cli.color.as_str() {
             "never" => {
-                LoreRenderer::init(ColorMode::Never);
+                LoreRenderer::init(ColorMode::Never, glyphs);
                 console::set_colors_enabled(false);
             }
             "always" => {
-                LoreRenderer::init(ColorMode::Always);
+                LoreRenderer::init(ColorMode::Always, glyphs);
                 console::set_colors_enabled(true);
             }
             "auto" => {
-                LoreRenderer::init(ColorMode::Auto);
+                LoreRenderer::init(ColorMode::Auto, glyphs);
             }
             other => {
-                LoreRenderer::init(ColorMode::Auto);
+                LoreRenderer::init(ColorMode::Auto, glyphs);
                 eprintln!("Warning: unknown color mode '{}', using auto", other);
             }
         }
@@ -409,21 +414,28 @@ fn handle_error(e: Box<dyn std::error::Error>, robot_mode: bool) -> ! {
             );
             std::process::exit(gi_error.exit_code());
         } else {
-            eprintln!("{} {}", Theme::error().render("Error:"), gi_error);
+            eprintln!();
+            eprintln!(
+                "  {}  {}",
+                Theme::error().render(Icons::error()),
+                Theme::error().bold().render(&gi_error.to_string())
+            );
             if let Some(suggestion) = gi_error.suggestion() {
-                eprintln!("{} {}", Theme::warning().render("Hint:"), suggestion);
+                eprintln!();
+                eprintln!("     {suggestion}");
             }
             let actions = gi_error.actions();
             if !actions.is_empty() {
                 eprintln!();
                 for action in &actions {
                     eprintln!(
-                        "  {} {}",
-                        Theme::dim().render("$"),
+                        "     {} {}",
+                        Theme::dim().render("\u{2192}"),
                         Theme::bold().render(action)
                     );
                 }
             }
+            eprintln!();
             std::process::exit(gi_error.exit_code());
         }
     }
@@ -443,7 +455,13 @@ fn handle_error(e: Box<dyn std::error::Error>, robot_mode: bool) -> ! {
             })
         );
     } else {
-        eprintln!("{} {}", Theme::error().render("Error:"), e);
+        eprintln!();
+        eprintln!(
+            "  {}  {}",
+            Theme::error().render(Icons::error()),
+            Theme::error().bold().render(&e.to_string())
+        );
+        eprintln!();
     }
     std::process::exit(1);
 }
@@ -1966,7 +1984,6 @@ async fn handle_embed(
     args: EmbedArgs,
     robot_mode: bool,
 ) -> Result<(), Box<dyn std::error::Error>> {
-    use indicatif::{ProgressBar, ProgressStyle};
     use std::sync::Arc;
     use std::sync::atomic::{AtomicBool, Ordering};
 
@@ -1985,18 +2002,7 @@ async fn handle_embed(
         std::process::exit(130);
     });
 
-    let embed_bar = if robot_mode {
-        ProgressBar::hidden()
-    } else {
-        let b = lore::cli::progress::multi().add(ProgressBar::new(0));
-        b.set_style(
-            ProgressStyle::default_bar()
-                .template("  {spinner:.blue} Generating embeddings [{bar:30.cyan/dim}] {pos}/{len}")
-                .unwrap()
-                .progress_chars("=> "),
-        );
-        b
-    };
+    let embed_bar = lore::cli::progress::nested_progress("Embedding", 0, robot_mode);
     let bar_clone = embed_bar.clone();
     let tick_started = Arc::new(AtomicBool::new(false));
     let tick_clone = Arc::clone(&tick_started);