- Add `WARPBOX_RESUMABLE_CHUNK_MODE` and `WARPBOX_RESUMABLE_CHUNK_PATH` environment variables to configure temporary chunk storage.
- Implement strict file validation for resuming uploads to ensure selected files match the pending session's metadata.
- Add `PLANS.md` to document development stages, roadmap, and API specifications (including batching and resumable flows).
Implement a native chunked resumable upload API and frontend integration
to support reliable large file uploads.
Changes include:
- Added a 3-step resumable upload API flow (create session, upload chunks, complete session).
- Introduced configuration options for chunk size, retention hours, and toggling the feature.
- Updated the frontend to utilize resumable uploads with progress tracking.
- Configured temporary chunk storage under `data/tmp/uploads` with automatic cleanup.
- Documented the API flow and configuration in the README.
