feat: comprehensive codebase improvements (cleanup, logic, performance)

Code Cleanups:
- Consolidated PlanTaskStatus and TddPhase types to types.ts
- Standardized node: prefix for Node.js builtin imports
- Fixed timer type to NodeJS.Timeout in respawn-controller

Logic Improvements:
- Fixed AI check race condition with UUID tracking in respawn-controller
- Added comprehensive _isStopped guards in session timer callbacks
- Made RalphTracker reset events non-reentrant via process.nextTick()
- Improved SessionManager mutex pattern reliability

Performance Optimizations:
- Fixed pendingToolCalls memory leak with TTL cleanup in subagent-watcher
- Improved LRUMap.newest() from O(n) to O(1) with _newestKey tracking

Documentation:
- Enhanced README antiflicker section with 6-layer technical details

Version: 0.1441

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/web/public/app.js

@@ -11243,6 +11243,21 @@ class ClaudemanApp {
       this.planGenerationAbortController = null;
     }
 
+    // Clean up wizard-specific timers (leak fix: not cleared on SSE reconnect)
+    if (this.wizardMinimizedTimer) {
+      clearInterval(this.wizardMinimizedTimer);
+      this.wizardMinimizedTimer = null;
+    }
+
+    // Clean up wizard drag listeners (leak fix: document-level handlers)
+    this.cleanupWizardDragging();
+
+    // Deactivate focus trap if wizard was open (leak fix: keydown listener)
+    if (this.activeFocusTrap) {
+      this.activeFocusTrap.deactivate();
+      this.activeFocusTrap = null;
+    }
+
     // Clear minimized agents tracking
     this.minimizedSubagents.clear();