feat(hooks): register PreCompact event in hooks.json

plugins/llm-security/hooks/hooks.json

@@ -77,6 +77,17 @@
           }
         ]
       }
+    ],
+    "PreCompact": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "node ${CLAUDE_PLUGIN_ROOT}/hooks/scripts/pre-compact-scan.mjs"
+          }
+        ]
+      }
     ]
   }
 }