Address third-round PR review (comments + doc)

- `listItemsByStage`: the "also surface slugs absent from the index"
  clause in the comment was never actually implemented — the loop only
  iterates index-known slugs. Rewrote the comment to describe what the
  code does; callers needing orphan-detection can scan the items dir.
- `getItemStage`: added a comment explaining why the staleness guard
  (used elsewhere for ralph suppression) deliberately doesn't apply
  here. The last stage the agent wrote is still the correct stage even
  if the process later crashed — nothing auto-reverts, so no staleness
  check is appropriate.

Skipping the sync-I/O-in-useMemo concern (pre-existing, separate
project) and the ROWS_PER_ITEM=4 interaction with the 4-line selected
card (acceptable UX trade-off for showing the full 200-char
brief_description).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: promptium-ai

src/services/TrackerService.ts

@@ -595,6 +595,10 @@ export class TrackerService {
   // (which is the live self-report), then falls back to index.json bucket
   // membership, then to 'backlog' if the slug is unknown. Never returns null
   // for a known slug — an item always has a stage somewhere.
+  // The staleness guard used by ralph (`isItemWaiting`) deliberately doesn't
+  // apply here: the last stage the agent wrote is still the correct stage
+  // even if the agent crashed 48h ago — nothing would auto-revert it — so
+  // stage reads trust status.json unconditionally.
   getItemStage(projectPath: string, slug: string): TrackerStage {
     const status = this.getItemStatus(projectPath, slug);
     if (status) return status.stage;
@@ -605,15 +609,14 @@ export class TrackerService {
   // Enumerate every known active item grouped by stage. Stage for each slug
   // comes from status.json first; unmigrated items fall back to the index
   // buckets. Archived items are listed verbatim from index.archive.
+  // Maps each index-known slug to its canonical stage, with any fresh
+  // status.json stage overriding the index bucket. Slugs that exist only in
+  // tracker/items/<slug>/ but aren't yet in the index aren't surfaced —
+  // callers that need orphan-detection should scan the directory themselves.
   listItemsByStage(projectPath: string): Map<string, TrackerStage> {
     const index = this.readIndex(projectPath);
     const out = this.createStageBySlug(index);
-    // Override with status.json where present, so the agent's live self-report
-    // wins over the index buckets.
-    const knownSlugs = new Set(out.keys());
-    // Also surface slugs that have a status.json but aren't in the index yet
-    // (e.g., an agent wrote status.json before the index was updated).
-    for (const slug of knownSlugs) {
+    for (const slug of out.keys()) {
       const status = this.getItemStatus(projectPath, slug);
       if (status) out.set(slug, status.stage);
     }