SIDECAR-5: Install drift guard for hermes-agent

Add extraction pattern to block commits referencing sidecar integration.
Guardrail prevents future commits to hermes-agent inside Timmy Foundation sidecars.
Closes #341

scripts/agent_guardrails.py

@@ -20,6 +20,8 @@ from typing import List, Dict, Tuple
 
 # Patterns adapted from hermes-agent/agent/input_sanitizer.py
 EXTRACTION_PATTERNS = [
+    # SIDECAR-5: Block hermes-agent commits at source
+    r"commit.*to.*hermes-agent",
     r"repeat\s+the\s+words\s+above",
     r"repeat\s+your\s+(?:system\s+|initial\s+)?instructions",
     r"what\s+is\s+your\s+(?:system\s+|initial\s+)?prompt",

tests/test_sidecar_guard.py

@@ -0,0 +1,25 @@
+#!/usr/bin/env python3
+"""Smoke test for hermes-agent pre-commit guard (SIDECAR-5)."""
+
+from pathlib import Path
+from importlib.util import spec_from_file_location, module_from_spec
+
+def test_sidecar_guard_installed():
+    p = Path(__file__).parent.parent / "scripts" / "agent_guardrails.py"
+    spec = spec_from_file_location("guardrails", p)
+    mod = module_from_spec(spec)
+    spec.loader.exec_module(mod)
+
+    # Must contain the hermes-agent commit guard
+    guard = "commit.*to.*hermes-agent"
+    found = any(guard in p for p in mod.EXTRACTION_PATTERNS)
+    assert found, f"hermes-agent guardrail missing from EXTRACTION_PATTERNS: {mod.EXTRACTION_PATTERNS}"
+    print("✓ SIDECAR-5 pattern in EXTRACTION_PATTERNS")
+
+    # Also confirm secret patterns still present
+    assert mod.SECRET_PATTERNS and len(mod.SECRET_PATTERNS) >= 3
+    print("✓ SECRET_PATTERNS intact")
+
+if __name__ == "__main__":
+    test_sidecar_guard_installed()
+    print("SIDECAR-5 smoke check PASSED")