#4 Issue 4: [API] Course Upload & Transcoding

[elizabetheonoja-art]

Description:
Instructors upload raw MP4s. Transcode them to HLS (m3u8) for adaptive bitrate streaming.

Acceptance Criteria:

[ ] Upload endpoint POST /api/upload.

[ ] Integration with AWS MediaConvert or Mux.

[ ] Webhook handler for transcoding completion.

Priority: High
Labels: video, infrastructure