refactor(empty-state): 空状态支持内容居中

test/empty_state/empty_state_test.dart

@@ -69,7 +69,7 @@ void main() {
     semantics.dispose();
   });
 
-  testWidgets('should_render_compact_dimensions_for_embedded_empty_state', (
+  testWidgets('should_keep_standard_icon_size_in_compact_empty_state', (
     tester,
   ) async {
     await _pump(
@@ -83,7 +83,7 @@ void main() {
 
     expect(
       tester.getSize(find.byKey(const Key('empty-state-icon'))),
-      const Size(44, 44),
+      const Size(72, 72),
     );
     expect(find.byType(DecoratedBox), findsNothing);
     expect(
@@ -97,7 +97,7 @@ void main() {
       tester
           .widget<Padding>(find.byKey(const Key('empty-state-padding')))
           .padding,
-      const EdgeInsets.symmetric(horizontal: 16, vertical: 16),
+      const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
     );
     expect(find.byKey(const Key('empty-state-action')), findsNothing);
   });

test/library/favorites_page_test.dart

@@ -174,6 +174,14 @@ void main() {
 
     expect(find.byKey(const Key('favorites-empty')), findsOneWidget);
     expect(find.byType(EmptyState), findsOneWidget);
+    final viewport = tester.getRect(
+      find.byKey(const Key('favorites-empty-scroll')),
+    );
+    final content = tester.getRect(
+      find.byKey(const Key('empty-state-content')),
+    );
+    expect(content.center.dx, closeTo(viewport.center.dx, 0.1));
+    expect(content.center.dy, closeTo(viewport.center.dy, 0.1));
   });
 
   testWidgets('should_show_retry_when_favorite_list_fails', (tester) async {

test/watch/watch_records_page_test.dart

@@ -209,6 +209,27 @@ void main() {
     expect(find.text('The Signal'), findsOneWidget);
   });
 
+  testWidgets('should_center_empty_state_in_remaining_page_space', (
+    tester,
+  ) async {
+    final auth = await _auth(signedIn: true);
+    await _pumpPage(
+      tester,
+      auth: auth,
+      history: CountingWatchHistory(const []),
+      catalog: FakeCatalogRepository(),
+    );
+
+    final viewport = tester.getRect(
+      find.byKey(const Key('watch-records-empty-scroll')),
+    );
+    final content = tester.getRect(
+      find.byKey(const Key('empty-state-content')),
+    );
+    expect(content.center.dx, closeTo(viewport.center.dx, 0.1));
+    expect(content.center.dy, closeTo(viewport.center.dy, 0.1));
+  });
+
   testWidgets('should_remove_and_clear_device_history_when_signed_out', (
     tester,
   ) async {