Integration & Testing Tasks - Signer Service/SDK

**Create Comprehensive Integration Tests**
Build end-to-end tests that verify the entire certificate lifecycle works correctly. Use real SSH servers in containers to test actual certificate authentication and ensure CA rotation doesn't break existing connections.

**Add Performance and Load Testing**
Create tests that simulate high load to ensure the service can handle many concurrent certificate requests. Test performance during CA rotation and identify bottlenecks that need optimization.

Start by locating the signer service/SDK certificate-lifecycle code and the existing integration-test setup. Run the current tests, then determine how to add containerized SSH authentication and concurrent request coverage; done means the lifecycle, CA rotation, existing connections, and load behavior are tested.

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