note: Lifecycle client requires explicit local stdio MCP config/trust policy. `00001KVHR3WRF` is queued and not yet implemented; leave this Ticket queued until that dependency is closed.

author: yoi-orchestrator


summary: Configured local stdio MCP serverを明示 config から起動し、newline-delimited JSON-RPC over stdioで initialize/capability negotiation/initialized notification/shutdownを行う lifecycle client foundation を実装する。Tools/resources/prompts registration/executionは後続 Ticket のため含めない。

role_plan: Orchestrator は acceptance records を commit 後、専用 implementation worktree `.worktree/00001KVHR3WRY-mcp-stdio-lifecycle-client` を作成し、Coder をその child worktree への narrow write scope で起動する。Coder 実装後、Reviewer が process lifecycle safety、JSON-RPC framing、initialize/capability negotiation、stderr bounds/redaction、shutdown/kill fallback、no ToolRegistry/resources/prompts exposure を確認する。