[abruption]

Adds optional stdio MCP tools for listing and messaging configured Claude/Codex destinations, plus a repository-local Codex plugin. Default policy permits local listing only; explicit configuration grants send and pins SSH routes/Codex homes. CLI results, partial failures and Reply-To self-host normalization are preserved. A shared MCP process does not advertise its launcher's session as the caller.

Refs #46. First of two PRs; depends on #76 (included until it merges). Explicit native wake follows in #78.

Validation:

• 259 tests with MCP extra; dependency-free suite passes with two optional protocol tests skipped.
• Real stdio client checks schemas, policy rejection, partial list failure and a Unix inbox receiving exactly one message.
• Real Codex 0.154.0 MCP client lists and sends to isolated local and KR SSH Claude-protocol fixture inboxes; both receive one message. Local and macbook Codex list/send also exercised with feat: add explicit bounded Codex wake (#46) #78's native activation layer, including the Orca custom home.
• Existing client approval refusal was verified. Successful tests explicitly authorized only the test send tool and destinations in isolated client configuration; the plugin does not grant that approval.
• Wheel+MCP and standalone sdist installation, plugin manifest validation, and actual marketplace/plugin installation in disposable CODEX_HOME pass. CI includes Python 3.10/3.13 Linux/macOS MCP jobs plus the existing core/package/install checks.

Python 3.9 standalone dependencies and install.sh remain unchanged. MCP requires Python 3.10+. No release or production plugin configuration changes.