- Extend API /folders endpoint to support browsing subdirectories with path parameter
- Add depth and has_children fields to FolderItem
- Create FolderBrowser component with tree view navigation
- Create FolderPicker component with input, browse button and popup modal
- Add API proxy route for /api/folders
- Update LibraryForm to use new FolderPicker component
- Fix path handling to correctly resolve /libraries/ subdirectories
- Removed space-y-6 container wrapper
- Added explicit mb-6 margins on breadcrumb, h1, Card, and h2 elements
- Consistent spacing approach across all library pages