feat(handler): add support for processing and uploading gif videos to S3

[peter064226]

Add logic to handle gif video outputs from ComfyUI nodes, including uploading to S3 bucket and cleaning up local files. The implementation follows the same pattern as image handling but with video-specific content type handling.

Motivation

​​User Demand​​: Support animated outputs (e.g., GIFs/MP4s) from video-generation nodes (e.g., AnimateDiff, GIF-compatible savers).
​​Scalability​​: Videos are larger than images and require dedicated S3 handling (e.g., multipart uploads for big files).
​​Maintenance​​: Unify media-handling logic (images + videos) to reduce tech debt.

[TimPietruskyRunPod]

Good direction — handling gifs (which ComfyUI uses for video/gif outputs, e.g. from ComfyUI-VideoHelperSuite or AnimateDiff) alongside images is a real gap in the current handler. Approving the concept, but several things need to change before merge:

Blocking

1. Rebase required — the branch is behind main and conflicts. Several things have moved since you opened this (e.g. PR #197 added a process-liveness check, the response structure was clarified in #157's investigation).
2. Variable rename is unnecessary and noisy — splitting output_data into output_data_images and output_data_videos adds churn for no functional benefit. The final response can just be:

   if output_data_images: final_result["images"] = output_data_images
   if output_data_videos: final_result["videos"] = output_data_videos

   …without renaming the existing images accumulator. Please keep output_data as the images list and introduce a new output_data_videos only.
3. Hardcoded prefix=f"comfy/{job_id}" for video S3 uploads is inconsistent with how images are uploaded (which just uses rp_upload.upload_image(job_id, ...)). And it conflicts with #191 which is adding configurable BUCKET_PREFIX. Please align — either:
   • Use the same BUCKET_PREFIX env var (preferred), or
   • Use rp_upload.upload_image for symmetry.
4. extra_args={"ContentType": f"video/{filename.split('.')[-1]}"} is dangerous: a .webp will become video/webp, .png will become video/png, etc. Either map known extensions (mp4, webm, gif, mov) to their MIME types explicitly, or skip the ContentType arg and let boto3 detect.
5. No changeset — please add .changeset/feat-handle-video-outputs.md:

   ---
   "worker-comfyui": minor
   ---
   
   feat: detect `gifs` output entries from video/animation nodes (AnimateDiff, VideoHelperSuite, etc.) and return them as base64 or upload to S3 alongside images.

Non-blocking

6. The local cleanup of os.remove(file_location) happens before checking that the S3 upload succeeded. If S3 upload throws, the original file is gone and we lose recoverability. Use try/finally like the image path does.

Happy to merge once the rebase and the items above are addressed. The feature itself is wanted.