feature: active downloads dashboard for server admins

[AciDCooL]

Hey everyone.

So i really like the offline sync feature in moonfin, but as a server admin it was driving me crazy that i had zero visibility into the background transcodes. since they don't show up in the normal jellyfin dashboard, you basically have no idea if someone is hammering your cpu/gpu with downloads.

I decided to build an "Active Downloads" tab right into the moonfin plugin config page to fix this. it hooks into jellyfin's internal transcode manager and surfaces all the active background jobs in real-time.

what's in it:
• speed (fps) and eta
• target bitrate
• a hardware acceleration badge if it detects vaapi/nvenc/qsv in the ffmpeg args
• a cancel button so you can kill runaway jobs if someone is syncing a whole library (note: because of how the http stream works, if you cancel it from the server, the client will just assume it finished and keep the partial file, but at least your server load drops instantly).

i made a test release on my fork if anyone wants to try it out on their own setup before i submit an official pr for this:
v1.9.1.1-activeDownloads

let me know what you think.

[RadicalMuffinMan]

Neat, can you update your fork with the commits so I can take a look? Then we can look into doing a PR for this upcoming release

[AciDCooL]

I just did and updated the manifest if that makes it easier for testing. But I should not forget to exclude the manifest in the PR *mentalnote

[RadicalMuffinMan]

go ahead and make the PR when you get a chance and we can see about adding it, I know a few people have asked for it