P4.4: killTeamSession + cleanup_team wiring (multiplexer Phase 4)

[takemo101]

Phase 4, issue P4.4 — part of the multiplexer backend abstraction implementation plan.

Design: docs/designs/cuekit-multiplexer-backend-design.md

Prerequisites: P4.3 merged.

Outcome

MultiplexerBackend gets an optional killTeamSession(team_id). ZellijBackend implements it as kill-sessions cuekit-team-<id>. The MCP cleanup_team handler calls it after individual cleanups.

Files

• Modify: packages/adapters/src/multiplexer-backend.ts
• Modify: packages/adapters/src/zellij-backend.ts
• Modify: packages/mcp/src/* (the cleanup_team handler — locate via grep)

Steps

• Add killTeamSession?(team_id): Promise<void> to interface.
• ZellijBackend.killTeamSession: issue kill-sessions.
• cleanup_team handler: after looping cleanup of member tasks, call backend.killTeamSession?.(team_id).

Acceptance

Integration test: after cleanup_team, the zellij session is gone (zellij list-sessions does not list it).