- Created a detailed \`docs\` directory with Chinese documentation for all major features.
- Implemented \`BaseContext\` propagation in \`Engine\` to allow long-lived connections (like SSE) to receive shutdown signals.
- Added \`Engine.Context()\` to provide access to the shutdown context.
- Updated \`docs/sse.md\` with a guide on handling graceful shutdowns.
- Cleaned up temporary build/update scripts.
Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
