5.1 Instance lifecycle and actions

# 5.1 Instance lifecycle and actions

**Parent:** Story 5 (#7232)
**Tool file:** `forge/ee/lib/mcp/tools/instances.js` (extend), `forge/ee/lib/mcp/tools/devices.js` (extend)

## Summary

Let an agent run and manage the lifecycle of hosted instances and remote instances (devices). This is the highest-value gap: agents can create an instance today but cannot start, stop, or delete it. Non-destructive state changes are consolidated into single action tools; destructive operations (delete, rollback) are separate tools with `destructiveHint: true`.

Start with forge/ee/lib/mcp/tools/instances.js and forge/ee/lib/mcp/tools/devices.js, reading the existing creation tools and their lifecycle-related conventions. Extend both tool files so agents can manage hosted and remote instance lifecycles, consolidating non-destructive actions and separating delete and rollback with destructiveHint: true. Done means the specified lifecycle operations are exposed consistently for both instance types.

Written by the indexing model from the issue text.