Merge main into refactor/frontend

Merge latest features from main including:
- PR #161 (worktree-confusion): Clarified branch handling in dialogs
- PR #160 (speckits-rebase): Planning mode functionality

Resolved conflicts:
- add-feature-dialog.tsx: Combined TanStack Router navigation with branch selection state
- worktree-integration.spec.ts: Updated tests for new worktree behavior (created at execution time)
- package-lock.json: Regenerated after merge

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docs/server/route-organization.md

@@ -582,3 +582,4 @@ The route organization pattern provides:
 Apply this pattern to all route modules for consistency and improved code quality.
 
 
+