Replace blocking A2A calls with streaming: webhook returns
immediate "Processing..." response, then streams results from
A2A agent and pushes them to Google Chat via REST API.
- Add ChatApiClient for proactive messaging via Chat REST API
- Add sendMessageStream() to A2ABridgeClient for SSE streaming
- Add extractFromStreamEvent() for parsing individual stream events
- Refactor handler to fire-and-forget async processing
- Fix isTerminal logic to use stream state instead of taskId presence
- Add asyncProcessing guard to prevent overlapping requests
- Add comprehensive README with deployment and setup guide
Adam Weidman