The MCP package requires Python 3.10 or higher. Updated:
- GitHub Actions workflow to test Python 3.10, 3.11, 3.12
- README.md badge to Python 3.10+
- CLAUDE.md prerequisites
- CONTRIBUTING.md prerequisites
- docs/MCP_SETUP.md prerequisites
This fixes the MCP installation error in CI:
'ERROR: No matching distribution found for mcp>=1.0.0'
MCP package versions 0.9.1+ all require Python 3.10+.