feat(tui): Phase 3 power features — Who, Search, Timeline, Trace, File History screens

Complete TUI Phase 3 implementation with all 5 power feature screens:

- Who screen: 5 modes (expert/workload/reviews/active/overlap) with
  mode tabs, input bar, result rendering, and hint bar
- Search screen: full-text search with result list and scoring display
- Timeline screen: chronological event feed with time-relative display
- Trace screen: file provenance chains with expand/collapse, rename
  tracking, and linked issues/discussions
- File History screen: per-file MR timeline with rename chain display
  and discussion snippets

Also includes:
- Command palette overlay (fuzzy search)
- Bootstrap screen (initial sync flow)
- Action layer split from monolithic action.rs to per-screen modules
- Entity and render cache infrastructure
- Shared who_types module in core crate
- All screens wired into view/mod.rs dispatch
- 597 tests passing, clippy clean (pedantic + nursery), fmt clean

crates/lore-tui/src/view/issue_detail.rs

@@ -295,7 +295,7 @@ fn render_metadata_row(
     if !meta.labels.is_empty() {
         cx = frame.print_text_clipped(cx, y, " | ", muted_style, max_x);
         let labels_text = meta.labels.join(", ");
-        let _ = frame.print_text_clipped(cx, y, &labels_text, muted_style, max_x);
+        cx = frame.print_text_clipped(cx, y, &labels_text, muted_style, max_x);
     }
 
     if !meta.assignees.is_empty() {