* feat(upload): implement optimistic UI for file uploads and enhance message handling
* feat(middleware): enhance file handling by collecting historical uploads from directory
* feat(thread-title): update page title handling for new threads and improve loading state
* feat(uploads-middleware): enhance file extraction by verifying file existence in uploads directory
* feat(thread-stream): update file path reference to use virtual_path for uploads
* feat(tests): add core behaviour tests for UploadsMiddleware
* feat(tests): remove unused pytest import from test_uploads_middleware_core_logic.py
* feat: enhance file upload handling and localization support
- Update UploadsMiddleware to validate filenames more robustly.
- Modify MessageListItem to parse uploaded files from raw content for backward compatibility.
- Add localization for uploading messages in English and Chinese.
- Introduce parseUploadedFiles utility to extract uploaded files from message content.