Expose rooms to external agents via A2A and MCP

Expose rooms through A2A as the standard agent-to-agent interface, including discovery through Agent Cards, task delegation, streaming, and structured artifacts. Provide MCP alongside it as a compatibility layer for harnesses that consume rooms as tools or resources.

This lets existing MCP clients consult rooms while giving peer agents a protocol designed for discovery and long-running collaboration.

Start by locating the repository’s existing MCP integration and the entry points for rooms and agents. Compare those capabilities with the requested A2A discovery, delegation, streaming, and structured artifacts; done means rooms are exposed through both interfaces for the stated client and peer-agent use cases.

Written by the indexing model from the issue text.