Release 0.4.30

[nimatime]

Summary

• Bump coordinated npm/PyPI release version to 0.4.30
• Update release notes for WWDC26 compiler support
• Sync README truth, metrics, MCP server metadata, Python SDK, and extension manifests

Verification

• npm run versions:check
• npm run metrics:check
• npm run docs:check
• npm run release:check
• npm run typecheck
• npm run lint
• npm run build
• npm test
• npm run typecheck:examples
• npm run boundary:check
• npm audit --audit-level=moderate
• python3 -m pip install -e '.[dev]'
• python3 -m pytest -v
• python3 -m build