fix(ui): render the exact production version

tests/test_runtime_role_and_performance.py

@@ -112,3 +112,12 @@ def test_login_first_viewport_has_no_third_party_or_inline_styles():
     assert "css/page-login.css" in template
     assert "gradient(" not in stylesheet
     assert "font-size: clamp" not in stylesheet
+
+
+def test_login_version_uses_single_app_config_truth():
+    app_source = (ROOT / "app.py").read_text(encoding="utf-8")
+    template = (ROOT / "templates/login.html").read_text(encoding="utf-8")
+
+    assert "app.config['SYSTEM_VERSION'] = SYSTEM_VERSION" in app_source
+    assert template.count("config.get('SYSTEM_VERSION', '')") == 2
+    assert "EwoooC V{{" not in template