feat(home): 使用胶片盘图片导航图标

test/home/app_bottom_nav_test.dart

@@ -179,4 +179,29 @@ void main() {
       findsWidgets,
     );
   });
+
+  testWidgets('should_fallback_when_asset_icon_is_missing', (tester) async {
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Scaffold(
+          bottomNavigationBar: AppBottomNav(
+            items: [
+              AppBottomNavItem(
+                tabKey: const Key('tab-home'),
+                icon: Icons.theaters_outlined,
+                selectedIcon: Icons.theaters,
+                assetPath: 'assets/icon/missing_film_reel.png',
+                label: 'Home',
+                selected: true,
+                onTap: () {},
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    expect(find.byIcon(Icons.theaters_outlined), findsOneWidget);
+  });
 }