# Port Guard to Pi Dev Implementation

## Summary
Created pi dev extension at `plugins/automaton-guard-pi/` using the `@earendil-works/pi-coding-agent` API.

## Changes

### New Files
- `plugins/automaton-guard-pi/guard.ts` — Pre-edit guard for pi dev harness
  - Intercepts `tool_call` events for edit/write/bash tools
  - Calls `status.py --can-edit` before allowing file modifications
  - Handles stale task detection with user notification
  - Uses `child_process.execSync` for status.py invocation
- `plugins/automaton-guard-pi/package.json` — Package manifest with pi-coding-agent peer dependency

### Integration
- `scripts/register-guards.sh` — Detects `pi` in PATH and installs the guard via `pi install`
- `contracts/harness-integration.md` — Updated enforcement matrix to include Pi Dev