fix(security): the standing-audit double's unread object parameter is named _object

`tsconfig.test.json` runs with `noUnusedParameters`, and the engine-contract
patch introduced `update(object, data, options)` whose first argument the double
does not read — TS6133 in the test project only, which a src-only `tsc --noEmit`
cannot see. The parameter keeps its POSITION, because the object name is
argument one on every IDataEngine write door and dropping it would hand the
dispatch predicate the wrong arguments.

Co-Authored-By: Claude <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AhQASwqJr2Z7XfGWUdvnbF

Author: claude

packages/plugins/plugin-security/src/platform-admin-standing-audit.test.ts

@@ -119,7 +119,12 @@ function makeQl(
     // hand-mirrored guard (`check:engine-double-contract`): a fixture drifting
     // to a call shape ObjectQL.update would refuse fails loudly here. Nothing
     // in this file updates, and that is exactly why the refusal must be real.
-    async update(object: string, data: any, options?: any) {
+    //
+    // `_object` keeps the door's POSITION — the object name is argument one on
+    // every `IDataEngine` write — while telling `noUnusedParameters` that not
+    // reading it is deliberate. Dropping it would shift `data` and `options`
+    // one place left and hand the dispatch predicate the wrong arguments.
+    async update(_object: string, data: any, options?: any) {
       assertEngineUpdateDispatch(data, options);
       return null;
     },