Frontend: removed the forced MIME type from the Video.js sources object so it can correctly handle non-mp4 “regular” streams.

File: video-remote/src/components/VideoModal.tsx
Backend: updated /videos/{file_id}/stream-transcoded so that when a Range request is present, it computes an approximate duration_sec from the requested byte length and bitrate, and passes that to ffmpeg (so the response length aligns with Content-Length).

File: media-api/main.py

video-remote/src/components/VideoModal.tsx

@@ -52,7 +52,10 @@ export const VideoModal: React.FC<Props> = ({ fileId, onClose }) => {
       sources: [
         {
           src: src,
-          type: 'video/mp4'
+          // Do not hardcode the MIME type: the "regular" endpoint may serve
+          // non-mp4 containers (avi/mkv/etc), and forcing mp4 can trigger
+          // MEDIA_ERR_SRC_NOT_SUPPORTED in Video.js/browser.
+          // Let Video.js/browser sniff based on the actual response.
         }
       ]
     })