- Add tryRelinkOrphanedFeature() to find and link matching tasks
- Normalize titles (trim, lowercase, collapse whitespace) for matching
- Only relink when exactly one task matches (ambiguous = no action)
- Sync feature status from task state on successful relink
- Normalize to 'defined' when no safe relink exists
- Add 7 tests for orphaned feature relink scenarios
- All 57 tests passing
- Add ChatView component with sidebar navigation and message thread layout
- Add useChat hook with SSE streaming state management for real-time updates
- Add chat API functions for sessions and messages (create, list, send, stream)
- Add mobile-responsive CSS styles for chat interface
- Add tests for useChat hook and ChatView component
- Integrate chat into task view and navigation (Header, MobileNavBar)
