docs(32-03): complete loading state colocation plan

Tasks completed: 3/3
- Create JKResyncButton component
- Create JKVideoButton component
- Refactor JKSessionScreen to use extracted components

SUMMARY: .planning/phases/32-state-update-optimization/32-03-SUMMARY.md

.planning/STATE.md

@@ -10,11 +10,11 @@ See: .planning/PROJECT.md (updated 2026-03-03)
 ## Current Position
 
 Phase: 32 of 32 (State Update Optimization)
-Plan: 1 of 4 complete (Redundant Operations Fix)
+Plan: 3 of 4 complete (Loading State Colocation)
 Status: In progress
-Last activity: 2026-03-05 — Completed 32-01-PLAN.md
+Last activity: 2026-03-05 — Completed 32-03-PLAN.md
 
-Progress: [█████████░] 83%
+Progress: [█████████░] 85%
 
 ## Performance Metrics
 
@@ -26,8 +26,8 @@ Progress: [█████████░] 83%
 **v1.7 Performance Optimization (In Progress):**
 - Phases: 5 (phases 28-32)
 - Phases completed: 4 (Phases 28, 29, 30, 31)
-- Requirements: 19 (16 complete)
-- Plans completed: 8
+- Requirements: 19 (17 complete)
+- Plans completed: 9
 
 ## Accumulated Context
 
@@ -57,6 +57,8 @@ Recent decisions (v1.7):
 - 1.5s debounce delay for track sync covers mixer initialization window - 32-01
 - useDebounceCallback with ref pattern prevents stale closures - 32-01
 - useMemo with empty deps creates stable debounced function - 32-01
+- State colocation: Loading state lives in component that uses it - 32-03
+- React.memo on self-contained button components prevents parent re-renders - 32-03
 
 ### Investigation Findings (v1.7)
 
@@ -68,6 +70,7 @@ Recent decisions (v1.7):
 5. Debounce instance recreation on dependency change - FIXED (Phase 32-01)
 6. Missing React.memo on child components - FIXED (Phase 30)
 7. Redundant mixer categorization dispatches - FIXED (Phase 32-02)
+8. Loading state in parent causing unnecessary re-renders - FIXED (Phase 32-03)
 
 **Hotspot files:**
 - `useMixerStore.js:178-185` - VU update dispatch - FIXED
@@ -102,9 +105,9 @@ Recent decisions (v1.7):
 ## Session Continuity
 
 Last session: 2026-03-05
-Stopped at: Completed 32-01-PLAN.md (Redundant Operations Fix)
+Stopped at: Completed 32-03-PLAN.md (Loading State Colocation)
 Resume file: None
 
 **Next steps:**
-1. Continue Phase 32 execution with remaining plans
-2. Plan verification/performance testing when all optimizations complete
+1. Execute 32-04-PLAN.md (Final plan in Phase 32)
+2. Plan Phase 33 for verification/performance testing when all optimizations complete

.planning/phases/32-state-update-optimization/32-03-SUMMARY.md

@@ -0,0 +1,136 @@
+---
+phase: 32-state-update-optimization
+plan: 03
+subsystem: ui
+tags: [react, performance, state-colocation, memo]
+
+# Dependency graph
+requires:
+  - phase: 32-state-update-optimization
+    provides: Research identifying loading state re-renders as performance issue
+provides:
+  - Self-contained JKResyncButton component with colocated loading state
+  - Self-contained JKVideoButton component with colocated loading state
+  - Simplified JKSessionScreen without video/resync loading state
+affects: [future button components, state colocation patterns]
+
+# Tech tracking
+tech-stack:
+  added: []
+  patterns:
+    - "State colocation: Loading state lives in component that uses it"
+    - "React.memo wrapper on self-contained components"
+    - "PropTypes for component documentation"
+
+key-files:
+  created:
+    - jam-ui/src/components/client/JKResyncButton.js
+    - jam-ui/src/components/client/JKVideoButton.js
+  modified:
+    - jam-ui/src/components/client/JKSessionScreen.js
+
+key-decisions:
+  - "Colocated loading state in button components to prevent parent re-renders"
+  - "memo() wrapper on both buttons for render optimization"
+  - "Preserved original behavior: 10-second video timeout, silent resync success"
+
+patterns-established:
+  - "Button components with internal loading state pattern"
+  - "Parent passes callbacks, child manages UI state"
+  - "displayName for React DevTools debugging"
+
+# Metrics
+duration: 3min
+completed: 2026-03-05
+---
+
+# Phase 32 Plan 03: Loading State Colocation Summary
+
+**Extracted video and resync buttons with colocated loading state using React.memo, eliminating parent re-renders**
+
+## Performance
+
+- **Duration:** 3 minutes
+- **Started:** 2026-03-05T19:33:34Z
+- **Completed:** 2026-03-05T19:36:40Z
+- **Tasks:** 3
+- **Files modified:** 3
+
+## Accomplishments
+- Created self-contained JKResyncButton with local loading state
+- Created self-contained JKVideoButton with local loading state
+- Removed videoLoading and resyncLoading state from JKSessionScreen
+- Loading state changes no longer trigger parent re-renders
+- Simplified JKSessionScreen by 91 lines of code
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Create JKResyncButton component** - `e35bed21e` (feat)
+2. **Task 2: Create JKVideoButton component** - `207598940` (feat)
+3. **Task 3: Refactor JKSessionScreen to use extracted components** - `f5bd1b1cd` (refactor)
+
+## Files Created/Modified
+
+**Created:**
+- `jam-ui/src/components/client/JKResyncButton.js` - Self-contained resync button with colocated loading state, memo wrapper, error handling
+- `jam-ui/src/components/client/JKVideoButton.js` - Self-contained video button with colocated loading state, memo wrapper, 10-second timeout
+
+**Modified:**
+- `jam-ui/src/components/client/JKSessionScreen.js` - Uses new button components, removed videoLoading/resyncLoading state, removed handleVideoClick/handleResync functions, removed unused icon imports (-91 lines)
+
+## Decisions Made
+
+**1. State colocation over prop drilling**
+- Loading state lives in the button component that uses it
+- Parent doesn't need to know about loading state
+- Prevents parent re-renders when loading state changes
+- Follows Kent C. Dodds state colocation principle
+
+**2. memo() wrapper on both components**
+- Prevents re-renders from parent prop stability
+- Combined with colocated state = zero parent impact
+- displayName added for React DevTools debugging
+
+**3. Preserved original behavior**
+- Video button: 10-second loading timeout (prevents multiple clicks)
+- Resync button: Silent success, toast on error
+- Same error handling logic as original implementation
+- Same permission checks (canVideo, upgrade prompt)
+
+**4. PropTypes for documentation**
+- Documents expected props for maintainability
+- Runtime validation in development mode
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+
+None - straightforward extraction of button components with colocated state.
+
+## User Setup Required
+
+None - no external service configuration required.
+
+## Next Phase Readiness
+
+**Ready for:**
+- Phase 32 Plan 04: Debounce optimization (remove debounce recreation)
+- Further state colocation opportunities in other components
+
+**Performance impact:**
+- Eliminates 2 state updates triggering JKSessionScreen re-renders
+- Button loading states isolated to individual components
+- Part of comprehensive re-render reduction strategy (Phase 32)
+
+**Pattern established:**
+- Self-contained button components with local state
+- Can be replicated for other buttons with loading states
+- Example: record button, broadcast button, attach button
+
+---
+*Phase: 32-state-update-optimization*
+*Completed: 2026-03-05*