413 Content Too Large should show a clear upload-size error

Please improve error handling for oversized video/reference uploads.

I tried to start a Seedance generation with a video reference, but the request failed with a generic:

Failed to fetch (outerface.venice.ai)

The UI only showed an “Unexpected error” message.

After checking the browser network logs, the actual cause was:

413 Content Too Large

The reference video had been encoded to base64 and exceeded the request size limit.

This should be detected and shown clearly in the UI, for example:

“Reference file is too large. Please reduce the file size, resolution, bitrate, or duration and try again.”

Ideally, the frontend should also validate the payload size before sending the request, especially because base64 increases the effective request size.

This would save users from troubleshooting prompts, models, moderation, networking, or browser issues when the real problem is simply the upload size limit.