CI blocked: GitHub Actions disabled by account billing lock — enforce required status checks once resolved

[Roy-Wanyoike]

Context

All GitHub-hosted CI jobs fail with: 'The job was not started because your account is locked due to a billing issue.' This affects every PR on this repository regardless of content (public repos normally get free Actions — the lock is account-level, not repo-level).

Interim measure

Merges proceed only after local verification by the reviewing coordinator (go build / go vet / go test, migration validator), documented on each PR. Workflow files stay in place — CI activates automatically when billing is resolved.

Acceptance criteria

• Owner resolves the billing issue (Settings → Billing and plans)
• A trivial PR proves all CI jobs pass (Lint, Test, Migration validation)
• Ruleset 'main-branch-protection' upgraded to require passing status checks before merge
• Issue closed with evidence (link to a green run)