Hi @it_9582,
First and foremost, we don't recommend the "package promotion" feature as a means to indicate which "stage" (i.e. tested quality) a package is in relative to a CI/CD pipeline.
Instead, repackaging should be used:
https://docs.inedo.com/docs/proget/packages/repackaging
Having multiple feeds is fine; we do that for Products and PreReleaseProducts on proget.inedo.com, but that's to make it "harder" for someone to accidently use a prerelease version. Otherwise, you can just use one feed and have retention policies cleanup the "-ci" builds.
As for having the "build promotion" feature in ProGet be used as a workflow engine (i.e. to trigger actions upon promotion), I don't think we would consider that. At the most, we would do a webhook of sorts... though it doesn't make a ton of sense to be honest.
The reason is that ProGet isn't intended as the "source of truth" for build status - the idea is that you would have something like a pipeline in BuildMaster) update the statuses in ProGet.
The main benefit to having this status in ProGet is retention of builds/SBOMs.
Hope that helps,
Steve