[Feature] RomM as a Metadata Source

[ChaosBlades]

Is your feature request related to a problem? Please describe.
I have all my ROMs organized with RomM as my main collection yet if I for example move some ROMs over to Batocera or RetroDeck I have to search for metadata all over again via online sources. This both takes a lot of extra time and wastes these metadata services resources. Would need to go back again and fix bad artwork or metadata manually, manually match some things, fix incorrect matches, etc. Also the problem of having RomM, Batocera, RetroDeck, etc all running with the same ROMs all pulling the same images from these online sources. When you could just have one RomM instance pulling the new updated metadata then distributing that to Batocera, RetroDeck, etc. instead of downloading the same files 3+ times. Not to mention all the manual work mentioned.

Describe the solution you'd like
RomM to have a system with supporting documentation to allow developers to add RomM as a metadata source to there applications.

Additional context
I feel like this FR has to already be an existing request but I'm not seeing it. Maybe didn't search for the correct string of words. Also tried to see if this FR exists by asking Grok and it also can't find it which it has done a good job of in the past. Maybe this is a bad idea for some reason I can't think of. I feel like this would be an obvious thing someone would have thought of by this point. I know RomM has some compatibility between its file structure and others but this FR is a much cleaner solution.

[gantoine]

#1665

[vargash]

@ChaosBlades I found myself with the same question.
PR #2720 was a first try to make the gamelist.xml export usable out of the box with Batocera, when this lands on the public release you can try this and see if there's some cases missing.