[Issue]: Chapters are extracted twice

[enter-a-random-username]

Please describe your bug

In case a library uses instant gen chapter settings the chapters will be added (works as excepted, starts a lot of parallel processes).
On next "Extract chapter images" run the same files will get extracted again with a single process.

Reproduction Steps

1. As described in the bug report, check both chapter related boxes and add a file.
2. Add a file and monitor processes. Chapters will be generated.
3. Start the scheduled task, same file get extracted again.

Jellyfin Version

Unstable (master branch)

if other:

No response

Environment

- OS:
- Linux Kernel:
- Virtualization:
- Clients:
- Browser:
- FFmpeg Version:
- Playback Method:
- Hardware Acceleration:
- GPU Model:
- Plugins:
- Reverse Proxy:
- Base URL:
- Networking:
- Storage:

Jellyfin logs

No useful log, there no error/exception.

FFmpeg logs

No response

Please attach any browser or client logs here

No response

Please attach any screenshots here

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[jellyfin-bot]

Hi, it seems like your issue report has the following item(s) that need to be addressed:

• You have not filled in the environment completely.

This is an automated message, currently under testing. Please file an issue here if you encounter any problems.

[enter-a-random-username]

Hi, it seems like your issue report has the following item(s) that need to be addressed:

* You have not filled in the environment completely.

This is an automated message, currently under testing. Please file an issue here if you encounter any problems.

Yes, because it is not relevant. Not an client or software related issue, no crashes. There is no function on Dashboard to copy the server info.

[systemcrash]

See jellyfin/jellyfin-web#5436

[enter-a-random-username]

See jellyfin/jellyfin-web#5436

Nice, i know it is a bot and in cases that system is unrelated it is no use at all and gathering all the current. In my eyes it was a feature request and i do not like the feature page at all. Looks like a flash bomb, also nobody is active compared to forum and GitHub.

Sry, enough off-topic.

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Also this could be also extended, twice at the beginning and also every replace metadata with image triggers it. Jellysrub didn't do that. New trickplay improves a lot of things, but the unnecessary generation burns through a lot of resources.