chore: Improve service owner tests and add deletion jobs

[marikaner]

Context

This PR does the same as SAP/ai-sdk-js#1676 only for Java.

This improves the test setup as follows:

• security

  • service owners will now be added directly to a sub team with write access to the repo
  • secure important workflows with auth check, so that only maintainers can call those workflows

• branch deletion

  • branches under spec-update are deleted automatically after 90 days
  • branch deletion on service owner side triggers branch deletion for the according branch directly
  • we could change this to run on a branch instead of file + file_ref which seems a little weird to me

• refactoring

  • file and file-ref were renamed to service and ref

I did not apply the "auth check" to any jobs. It is up to you if you want to use this and where.

[newtork]

service owners will now be added directly to a sub team with write access to the repo

Are you saying, developers outside the java team have write access to the SAP Cloud SDK for AI for Java?

branches under spec-update are deleted automatically after 90 days

Was this aligned with the java team already? We already had long-running open PRs due to alignment / merge conflicts - e.g. grounding. Orchestration branch alignment may even take longer. 90 days seems long enough, but looks rather arbitrary to me.

[marikaner]

service owners will now be added directly to a sub team with write access to the repo

Are you saying, developers outside the java team have write access to the SAP Cloud SDK for AI for Java?

Yes, this is the minimum access needed to trigger workflows. Currently we share a PAT from an admin user, which is worse. @CharlesDuboisSAP and I already aligned on this.

branches under spec-update are deleted automatically after 90 days

Was this aligned with the java team already? We already had long-running open PRs due to alignment / merge conflicts - e.g. grounding. Orchestration may even be longer. 90 days seems arbitrary.

Yes 90 days is arbitrary and we didn't align on this. I chose 90 days because it is close to a quarter and I assume most cases will be more than covered by this.
Possible solutions:

• protect the branch if you need it longer than 90 days (but this is easy to forget)
• add exclude list (also easy to forget)
• increase duration