MCP compatibility

Conduit supports MCP 2026-07-28 with Streamable HTTP downstreams only. Supported operations are server/discover, tools/list, and terminal JSON tools/call. Request-scoped SSE/progress, stdio, legacy negotiation, prompts, resources, tasks, and subscriptions are unsupported.

Stateful downstream tool calls may return Mcp-Session-Id; Conduit performs at most one bounded cleanup DELETE using that invocation-owned session ID.