KiroCrew integration: typed CAO fleet control through cao-ops-mcp

Parent: #580

## Goal

Enable a KiroCrew agent to launch and manage CAO sessions through CAO's external typed control plane, without constructing shell commands or depending on CAO terminal context.

## Proposed approach

Provide a reference KiroCrew configuration that registers `cao-ops-mcp` and teaches the KiroCrew agent when to use its external fleet-management tools.

The integration should support these operator journeys:

- Discover available CAO profiles.
- Launch a CAO supervisor with an explicit profile, provider, working directory, session name, and initial task.
- Inspect session and terminal status.
- Send a follow-up instruction to the session supervisor.
- Read the latest supervisor or worker result when needed.
- Shut down a completed or abandoned session.

`cao-ops-mcp` must remain the model-initiated external control path. The integration must not use `handoff`, `assign`, or `send_message` from `cao-mcp-server` as substitutes; those tools require a terminal already managed by CAO.

## Scope

- Add a reference KiroCrew MCP server configuration for `cao-ops-mcp`.
- Add concise agent guidance for selecting CAO profiles and requiring an explicit working directory.
- Define stable linkage metadata between the originating KiroCrew conversation and the authoritative CAO session identity.
- Validate the control flow against a local CAO server.
- Document setup, expected failures, and cleanup.

## Acceptance criteria

- [ ] A KiroCrew agent can list available CAO profiles through `cao-ops-mcp`.
- [ ] A KiroCrew conversation can launch a named CAO session for a specified task and working directory.
- [ ] The returned CAO session and terminal identifiers are retained as linkage metadata, not copied runtime state.
- [ ] The agent can inspect status and send a follow-up to the supervisor.
- [ ] The agent can read relevant output without bypassing the supervisor as the normal coordination path.
- [ ] The agent can shut down the linked CAO session.
- [ ] Missing server, unknown profile, invalid working directory, timeout, and already-terminated session failures produce actionable responses.
- [ ] The setup works without `CAO_TERMINAL_ID` in the KiroCrew process.
- [ ] Documentation distinguishes a KiroCrew conversation from a CAO session.

## Non-goals

- Rendering CAO fleet UI in KiroCrew. That is covered by the sibling MCP Apps/AG-UI issue.
- Treating CAO as a KiroCrew model provider.
- Reimplementing CAO session, terminal, delegation, or approval state in KiroCrew.
- Managing remote CAO authentication in the first slice.