feat: add health check endpoint for container orchestration

[drernie]

Summary

Implements a basic health check endpoint (/health) for the MCP server to support container orchestration systems like Kubernetes and Docker Compose.

Changes

• ✅ Add /health endpoint using FastMCP's custom_route decorator
• ✅ Health check handler returns server status, timestamp, and version info
• ✅ Transport-aware registration (only enabled for HTTP/SSE transports)
• ✅ Comprehensive unit and integration tests
• ✅ Updated Docker container test to verify health endpoint

Implementation Details

Health Check Response Format

{
  "status": "ok",
  "timestamp": "2024-01-15T10:30:00Z",
  "server": {
    "name": "quilt-mcp-server",
    "version": "1.0.0",
    "transport": "http"
  }
}

Transport Compatibility

• HTTP/SSE/Streamable-HTTP: Health endpoint registered at /health
• stdio: No HTTP endpoints (maintains compatibility)

Testing

• Unit tests for health check handler
• Integration tests for FastMCP registration
• Docker container test validates health endpoint
• All existing tests pass

Documentation

Complete specification documents created in spec/197-add-health-checks/:

• 01-requirements.md - User stories and acceptance criteria
• 02-analysis.md - Current state analysis
• 03-specifications.md - Desired end state
• 04-phases.md - Implementation roadmap

Future Phases

This PR implements Phase 1 of the health check feature. Future enhancements:

• Phase 2: Component health integration (AWS, Athena, packages)
• Phase 3: Advanced endpoints (/readiness, /liveness)
• Phase 4: Docker HEALTHCHECK and Kubernetes probe support

Fixes #197

🤖 Generated with Claude Code

Co-Authored-By: Claude [email protected]