Likely easier said then done, but why not separate infra out from shared vs dedicated hosts? Something like, actions will still run but at some degraded capacity, where actions and PRs are still at least functional.

My company has heavy handily moved from self-hosted version control system to github and now we’re suffering more outages. Though the self hosted system had less features, and we needed to maintain our own jenkins infrastructure for CI/CD, at least we really only suffered from very major cloud-provider level outages