WP-0016 finished: interactive registry maintain with llm-connect automation

Closes the registry maintenance loop from inside each domain repo:
interactive prompting for judgment calls, full automation for safe and
high-confidence changes, both backed by the llm-connect HTTP bridge.

- New modules: maintain.py, maintain_llm.py, patches.py, interactive.py
- Schema: schemas/registry-patch.schema.json
- CLI: reuse-surface maintain; establish --scaffold --hook
- Sibling templates: Makefile fragment, pre-commit hook
- Deterministic signal collectors extended; validate cwd auto-detect
- Docs, gap priority 28, SCOPE update
- Tests: test_maintain.py, test_interactive.py (59 pytest total)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

reuse_surface/establish.py

@@ -11,7 +11,9 @@ from typing import Any
 import yaml
 
 from reuse_surface.llm_bridge import request_registry_draft
-from reuse_surface.registry import load_index_at, registry_paths
+from reuse_surface.registry import ROOT, load_index_at, registry_paths
+
+HOOK_TEMPLATE = ROOT / "templates" / "git-hook.pre-commit.registry"
 
 SCAFFOLD_README = """# Capability Registry
 
@@ -80,6 +82,18 @@ def scaffold_registry(
     return created
 
 
+def install_registry_hook(repo_root: Path, *, force: bool = False) -> Path:
+    hook_path = repo_root / ".git" / "hooks" / "pre-commit"
+    if not (repo_root / ".git").is_dir():
+        raise ValueError(f"not a git repository: {repo_root}")
+    if hook_path.exists() and not force:
+        raise ValueError(f"hook already exists: {hook_path}; use --force to overwrite")
+    hook_path.parent.mkdir(parents=True, exist_ok=True)
+    hook_path.write_text(HOOK_TEMPLATE.read_text(encoding="utf-8"), encoding="utf-8")
+    hook_path.chmod(0o755)
+    return hook_path
+
+
 def scaffold_next_steps(repo_root: Path) -> str:
     return textwrap.dedent(
         f"""