Support reading multiple tracks with Enhanced RTMP

[cytrus224]

Which version are you using?

1.11.3

Which operating system are you using?

Windows amd64 standard

Describe how to replicate the issue

1. Start streaming with OBS and ERTMPv2 to mediamtx with few video tracks and one audio track
2. Mediamtx says that its publishing multiple tracks to your stream
3. Try ffmpeg -i rtmp://localhost:1935/test, it can only access 1 video track and 1 audio track. I've used ffmpeg build from master branch, since release one does not support ERTMPv2 multitrack.

Server logs

No response

Network dump

No response

[aler9]

Hello, this is more a feature request than a bug since Enhanced-RTMP support in FFmpeg has been added quite recently.

This can be implemented if we find a way to distinguish between traditional RTMP readers and Enhanced-RTMP readers, and we disable Enhanced-RTMP features for the former, otherwise there's the risk of breaking support for legacy clients.

[cytrus224]

Just FYI ffmpeg 8.0 was released and it includes support for ertmpv2 with multitrack