Main branch protection

@santisoler @lheagy I tried to add a branch protection rule to `aurora` but am told the rule is invalid.  Is this maybe a permissions thing? Could you try to enforce that `main` cannot be merged to without  a PR with at least 1 approval?

<img width="891" height="432" alt="Image" src="https://github.com/user-attachments/assets/3a4f9b1a-1f72-4aa1-96ae-b820fa27b2b7" />