feat: enhance worktree listing by scanning external directories

- Implemented a new function to scan the .worktrees directory for worktrees that may exist outside of git's management, allowing for better detection of externally created or corrupted worktrees.
- Updated the /list endpoint to include discovered worktrees in the response, improving the accuracy of the worktree listing.
- Added logging for discovered worktrees to aid in debugging and tracking.
- Cleaned up and organized imports in the list.ts file for better maintainability.

apps/ui/src/styles/themes/dark.css

@@ -1,6 +1,6 @@
 /* Dark Theme */
 
-.dark {
+:root.dark {
   /* Deep dark backgrounds - zinc-950 family */
   --background: oklch(0.04 0 0); /* zinc-950 */
   --background-50: oklch(0.04 0 0 / 0.5); /* zinc-950/50 */