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>

CLAUDE.md

@@ -16,7 +16,7 @@ When user says "COM":
 1. Increment version in BOTH `package.json` AND `CLAUDE.md`
 2. Run: `git add -A && git commit -m "chore: bump version to X.XXXX" && git push && npm run build && systemctl --user restart claudeman-web`
 
-**Version**: 0.1440 (must match `package.json`)
+**Version**: 0.1441 (must match `package.json`)
 
 ## Project Overview
 
@@ -256,10 +256,6 @@ Use `LRUMap` for bounded caches with eviction, `StaleExpirationMap` for TTL-base
 | `scripts/monitor-respawn.sh` | Monitor respawn state machine in real-time |
 | `scripts/postinstall.js` | npm postinstall hook for setup |
 
-## Deprecated Code
-
-The TUI (Terminal UI) has been removed in favor of the web interface. Files in `src/tui/` are excluded from compilation via `tsconfig.json`.
-
 ## Memory Leak Prevention
 
 Frontend runs long (24+ hour sessions); all Maps/timers must be cleaned up.