refactor: Valve mirror module, golden menu test, local and CI checks

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

.github/workflows/bundle.yml

@@ -40,7 +40,7 @@ jobs:
       - name: Check
         run: |
           bash -n dist/steamify.sh
-          python3 -m py_compile ui/steamify-ui
+          python3 -m py_compile ui/steamify-ui patches/*.py
 
       # shellcheck through an action that brings its own binary: GitHub's runner has it installed,
       # Gitea's act_runner image doesn't. One file per run, as before (the exceptions are the bundle's).