- Update file browser header styles to wrap cleanly on small screens and preserve readable truncated labels
- Increase mobile close-button hit area and keep close action visible within header actions layout
- Add responsive WorkspaceSelector constraints to prevent menu/trigger overflow on narrow viewports
- Add a regression test that verifies the mobile close button remains visible and clickable
- Add workspace file APIs and hooks for session-scoped file browsing
- Create WorkspaceSelector component for switching between workspaces
- Update FileBrowserModal with workspace mode and improved UX
- Add files button to header with workspace-aware file browsing
- Add session files indicator to task cards for quick file access
- Include comprehensive tests for all new components and hooks
