docs(02-02): complete thread frontend UI plan

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.planning/STATE.md

@@ -2,15 +2,15 @@
 gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
-status: in-progress
-stopped_at: Completed 02-01-PLAN.md
-last_updated: "2026-03-15T10:39:24Z"
-last_activity: 2026-03-15 — Completed 02-01 thread backend API
+status: executing
+stopped_at: Completed 02-02-PLAN.md
+last_updated: "2026-03-15T10:46:26Z"
+last_activity: 2026-03-15 — Completed 02-02 thread frontend UI
 progress:
   total_phases: 3
   completed_phases: 1
   total_plans: 7
-  completed_plans: 5
+  completed_plans: 6
   percent: 71
 ---
 
@@ -26,11 +26,11 @@ See: .planning/PROJECT.md (updated 2026-03-14)
 ## Current Position
 
 Phase: 2 of 3 (Planning Threads)
-Plan: 1 of 3 in current phase
+Plan: 2 of 3 in current phase
 Status: In progress
-Last activity: 2026-03-15 — Completed 02-01 thread backend API
+Last activity: 2026-03-15 — Completed 02-02 thread frontend UI
 
-Progress: [███████---] 71%
+Progress: [█████████░] 86%
 
 ## Performance Metrics
 
@@ -54,6 +54,7 @@ Progress: [███████---] 71%
 | Phase 01 P03 | 3min | 2 tasks | 16 files |
 | Phase 01 P04 | 3min | 2 tasks | 5 files |
 | Phase 02 P01 | 5min | 2 tasks | 9 files |
+| Phase 02 P02 | 4min | 2 tasks | 10 files |
 
 ## Accumulated Context
 
@@ -75,6 +76,9 @@ Recent decisions affecting current work:
 - [Phase 02-01]: Drizzle sql template literals use raw table.column refs in correlated subqueries (not interpolated)
 - [Phase 02-01]: Thread deletion collects candidate image filenames before cascade for filesystem cleanup
 - [Phase 02-01]: Resolution validates categoryId existence, falls back to Uncategorized (id=1)
+- [Phase 02-02]: Tab navigation uses URL search params (?tab=gear|planning) for shareable URLs
+- [Phase 02-02]: Candidate panel runs as separate SlideOutPanel instance with independent uiStore state
+- [Phase 02-02]: Resolution invalidates threads, items, and totals queries for cross-tab data freshness
 
 ### Pending Todos
 
@@ -87,6 +91,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-03-15T10:39:24Z
-Stopped at: Completed 02-01-PLAN.md
-Resume file: .planning/phases/02-planning-threads/02-01-SUMMARY.md
+Last session: 2026-03-15T10:46:26Z
+Stopped at: Completed 02-02-PLAN.md
+Resume file: .planning/phases/02-planning-threads/02-02-SUMMARY.md