MCR-3646 Harmonize edge cases and improve error and log messages of annotation based configuration

[toKrause]

Link to jira.

Pull Request Checklist (Author)

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Ticket & Documentation

• The issue in the ticket is clearly described and the solution is documented.
• Design decisions (if any) are explained.
• The ticket references the correct source and target branches.
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Feature & Improvement Specific Checks

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  • Yes: Is a migration required? If yes, describe it.
  • Breaking change is marked in the commit message.

Behavior of some edge cases changes. See ticket for complete list. Migration guide follows.

Testing

• I have tested the changes locally.
• The feature behaves as described in the ticket.
• Were existing tests modified?
  • Yes: explain the changes for reviewers.

See ticket. Code contains exhaustive list of tests cases.

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  • Old API is deprecated or a migration is documented.
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Multi-Repo Considerations

• Is an equivalent PR in MIR required?
  • If yes, is it already created?