### Task B3: Hook the validator into pre-commit

**Files:**
- Modify: `.pre-commit-config.yaml`

**Interfaces:**
- Produces: a local hook that runs `local/validate-patches.R` when the registry or patch files change.

- [ ] **Step 1: Add the hook**

Add a `repo: local` hook entry to `.pre-commit-config.yaml`:

```yaml
  - repo: local
    hooks:
      - id: validate-patches
        name: validate patch registry
        entry: Rscript local/validate-patches.R
        language: system
        files: ^local/patches/
        pass_filenames: false
```

- [ ] **Step 2: Verify the hook runs**

Run: `pre-commit run validate-patches --all-files`
Expected: hook passes (`Patch registry OK`).

- [ ] **Step 3: Commit**

```bash
git add .pre-commit-config.yaml
git commit -m "ci(patches): validate patch registry in pre-commit"
```

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