Adds molecule_agent.a2a_server.A2AServer — a bundled HTTP server that
receives inbound A2A calls so remote agents can receive work from the
platform without provisioning their own HTTP endpoint.
- A2AServer: threaded HTTPServer on POST /a2a/inbound
- Sync and async handlers both supported; async handlers run in a
dedicated event loop per call to avoid "no event loop in thread" errors
- 9 unit tests covering: lifecycle, routing, error handling, async path,
concurrent requests
- Exported from molecule_agent.__init__; client.py docstring updated
- Closes GitHub #14
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
