a5633681

By: Michael Lynch <git@mtlynch.io>

Reduce duplication in video upload code

Collapses duplication introduced by the video upload feature without
changing behavior:

- Fold the repeated ffmpeg/ffprobe run-and-wrap-error pattern into one
  runMediaCommand helper, and drop the per-transcode requireWebMEncoders
  pre-flight (ffmpeg already fails clearly on a missing encoder).
- Merge MarkMediaItemReady/MarkMediaItemFailed into UpdateMediaStatus.
- Extract a viewerID handler helper for the four identical viewer-lookup
  blocks in browse/media handlers.
- Express WriteConverted in terms of WriteProduced so the temp-file
  lifecycle lives in one place.
- Inline the single-use Processor.writeProduced wrapper.

Net non-test LOC drops by ~60 (123 deleted, 61 added).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Timeline