- Added `processSendFileUpload` function to handle file uploads for sends.
- Integrated JWT token creation and verification for secure file uploads.
- Updated `handleCreateFileSendV2` and `handleGetSendFileUpload` to use new upload URL generation.
- Refactored upload handling in `handleUploadSendFile` and `handlePublicUploadSendFile` to utilize the new upload process.
- Introduced `uploadDirectEncryptedPayload` for handling direct uploads with progress tracking.
- Enhanced API routes to support both POST and PUT methods for attachment uploads.
- Added localization strings for upload progress messages.
- Created utility functions for direct upload URL building and payload parsing.