docs(30-01): complete memoize container components plan

Tasks completed: 2/2
- Task 1: Wrap JKSessionAudioInputs with React.memo
- Task 2: Wrap JKSessionRemoteTracks with React.memo

SUMMARY: .planning/phases/30-component-memoization/30-01-SUMMARY.md

.planning/STATE.md

@@ -10,11 +10,11 @@ See: .planning/PROJECT.md (updated 2026-03-03)
 ## Current Position
 
 Phase: 30 of 32 (Component Memoization)
-Plan: Not started
-Status: Ready to plan
-Last activity: 2026-03-05 — Completed Phase 29 Context Optimization
+Plan: 1 of 2 (Memoize Container Components)
+Status: In progress
+Last activity: 2026-03-05 — Completed 30-01-PLAN.md
 
-Progress: [████░░░░░░] 40%
+Progress: [████░░░░░░] 42%
 
 ## Performance Metrics
 
@@ -26,8 +26,8 @@ Progress: [████░░░░░░] 40%
 **v1.7 Performance Optimization (In Progress):**
 - Phases: 5 (phases 28-32)
 - Phases completed: 2 (Phases 28, 29)
-- Requirements: 19 (6 complete)
-- Plans completed: 3
+- Requirements: 19 (7 complete)
+- Plans completed: 4
 
 ## Accumulated Context
 
@@ -50,6 +50,8 @@ Recent decisions (v1.7):
 - getMixer stabilization via useCallback prevents cascade of function recreations - 29-01
 - Context value memoization only effective when hook functions are stable - 29-01
 - React.memo on consumers completes the optimization chain - 29-01
+- Container component memoization completes memoization chain from Phase 29 - 30-01
+- Default shallow comparison sufficient when props are stable from upstream - 30-01
 
 ### Investigation Findings (v1.7)
 
@@ -93,8 +95,8 @@ Recent decisions (v1.7):
 ## Session Continuity
 
 Last session: 2026-03-05
-Stopped at: Completed Phase 29 Context Optimization
+Stopped at: Completed 30-01-PLAN.md
 Resume file: None
 
 **Next steps:**
-1. `/gsd:plan-phase 30` — plan Component Memoization phase
+1. Continue Phase 30 Component Memoization with plan 30-02

.planning/phases/30-component-memoization/30-01-SUMMARY.md

@@ -0,0 +1,175 @@
+---
+phase: 30-component-memoization
+plan: 01
+subsystem: session-ui
+tags: [react, performance, memo, re-render-optimization]
+requires:
+  - 29-context-optimization
+provides:
+  - memoized-container-components
+  - complete-memoization-chain
+affects:
+  - 30-02
+tech-stack:
+  added: []
+  patterns:
+    - React.memo for container components
+    - displayName for DevTools visibility
+key-files:
+  created: []
+  modified:
+    - jam-ui/src/components/client/JKSessionAudioInputs.js
+    - jam-ui/src/components/client/JKSessionRemoteTracks.js
+decisions:
+  - key: container-component-memoization
+    decision: Wrap JKSessionAudioInputs and JKSessionRemoteTracks with React.memo
+    rationale: Completes the memoization chain from Phase 29, prevents cascade re-renders from parent
+    alternatives: ["PureComponent (class-based)", "manual shouldComponentUpdate"]
+    impact: Containers skip re-renders when props are shallowly equal
+  - key: default-comparison
+    decision: Use default shallow comparison in React.memo
+    rationale: Props are already stable from Phase 29 context optimization
+    alternatives: ["custom comparison function"]
+    impact: Simpler code, relies on upstream prop stability
+metrics:
+  duration: 76 seconds
+  completed: 2026-03-05
+---
+
+# Phase 30 Plan 01: Memoize Container Components Summary
+
+**One-liner:** Wrapped JKSessionAudioInputs and JKSessionRemoteTracks with React.memo to prevent unnecessary re-renders when parent re-renders with unchanged props.
+
+## What Was Built
+
+### Component Memoization
+Wrapped two container components with React.memo following the Phase 29 pattern:
+
+1. **JKSessionAudioInputs**
+   - Added `memo` to React imports
+   - Wrapped with `memo(function JKSessionAudioInputs(...))`
+   - Added displayName for React DevTools visibility
+   - Prevents re-renders when myTracks, chat, mixerHelper, isRemote, mixType unchanged
+
+2. **JKSessionRemoteTracks**
+   - Added `memo` to React imports (alongside existing useMemo)
+   - Wrapped with `memo(function JKSessionRemoteTracks(...))`
+   - Added displayName for React DevTools visibility
+   - Prevents re-renders when mixerHelper and sessionModel unchanged
+
+### Memoization Chain
+Completes the optimization chain started in Phase 29:
+- **Phase 29:** Stabilized context values and hook functions with useCallback/useMemo
+- **Phase 30-01:** Memoized container components that receive those stable props
+- **Existing:** Child components (JKSessionMyTrack, SessionTrackVU, SessionTrackGain) already memoized
+
+Result: Parent re-renders no longer cascade through these components when props haven't changed.
+
+## Technical Decisions
+
+### Pattern Consistency
+Used the same memo pattern established in Phase 29:
+```javascript
+const ComponentName = memo(function ComponentName({ props }) {
+  // implementation
+});
+ComponentName.displayName = 'ComponentName';
+```
+
+### No Custom Comparison
+Did not add custom comparison functions because:
+- Props are already stable from Phase 29 context optimization
+- Default shallow comparison is sufficient
+- Simpler code, easier to maintain
+- Custom comparisons can mask upstream prop stability issues
+
+## Files Modified
+
+### jam-ui/src/components/client/JKSessionAudioInputs.js
+- Added `memo` to React imports
+- Wrapped component with `memo(function JKSessionAudioInputs)`
+- Added displayName for DevTools
+- Commit: `4dea95e85`
+
+### jam-ui/src/components/client/JKSessionRemoteTracks.js
+- Added `memo` to React imports (with useMemo)
+- Wrapped component with `memo(function JKSessionRemoteTracks)`
+- Added displayName for DevTools
+- Commit: `a26f75591`
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Testing Notes
+
+### Automated Verification
+- Syntax checks passed for both files
+- Pattern verification confirmed memo wrappers present
+- displayName properties added correctly
+
+### Manual Verification Available
+Users can verify with React DevTools:
+1. Open session screen in browser
+2. Open React DevTools Profiler tab
+3. Record while triggering parent re-render
+4. Check that JKSessionAudioInputs and JKSessionRemoteTracks show "Did not render" when props unchanged
+
+## Integration Points
+
+### Upstream Dependencies
+- Relies on Phase 29 context optimization for stable props
+- mixerHelper from SessionMixerContext (memoized in 29-01)
+- sessionModel passed from parent (stable reference)
+
+### Downstream Impact
+- Phase 30-02 can build on this foundation
+- Future phases benefit from complete memoization chain
+- Performance gains compound across optimization phases
+
+## Performance Impact
+
+### Re-render Prevention
+Before: JKSessionAudioInputs and JKSessionRemoteTracks re-rendered on every parent re-render
+After: Components skip re-renders when props are shallowly equal
+
+### Expected Benefit
+- Reduces wasted renders in session screen
+- Prevents unnecessary VU meter and track component updates
+- Complements Phase 28 VU store and Phase 29 context optimizations
+
+## Next Phase Readiness
+
+**Ready for Phase 30-02** ✅
+
+No blockers identified. Component memoization chain is complete:
+- Context values stable (Phase 29)
+- Container components memoized (Phase 30-01)
+- Child components already memoized (previous work)
+
+## Lessons Learned
+
+### Memoization Effectiveness
+React.memo only works when props are stable. Phase 29's context optimization was essential prerequisite.
+
+### Pattern Benefits
+- Named function expressions provide better stack traces
+- displayName improves debugging in React DevTools
+- Consistent pattern across codebase aids comprehension
+
+### Dependency Chain
+Performance optimizations often require coordinated changes:
+1. Stabilize data sources (Phase 28: VU store)
+2. Stabilize prop values (Phase 29: context memoization)
+3. Prevent re-renders (Phase 30: component memoization)
+
+## Commits
+
+| Hash      | Type     | Description                                      |
+|-----------|----------|--------------------------------------------------|
+| 4dea95e85 | refactor | wrap JKSessionAudioInputs with React.memo        |
+| a26f75591 | refactor | wrap JKSessionRemoteTracks with React.memo       |
+
+**Total commits:** 2
+**Total files modified:** 2
+**Execution time:** 76 seconds