Uptime and SSL alert policies

Summary

Currently, uptime and SSL certificate expiry alert policies are deployed at the Cloud Run service level because they are embedded in the gcp-cloud-run-app module through a child call to the gcp-site-monitoring module. This means we end up with multiple policies in projects which deploy multiple Cloud Run services.

To align with our current best practices, we should implement per-project alert policies within this module instead. These policies will:

• Capture all uptime checks and SSL certificates across the entire project.
• Aggregate conditions based on the specific resource that fails.

This approach will streamline alert configurations, reduce duplication, and optimise costs while maintaining comprehensive monitoring coverage.

Acceptance criteria

• Per-project alert policies are included in this module for uptime checks and SSL expiry.