fix(ui): align history search placeholder and prevent clipping

ui/flutter/test/features/tasks/presentation/history_search_field_test.dart

@@ -0,0 +1,59 @@
+import 'package:flutter/foundation.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:gopeed/features/tasks/presentation/widgets/history_search_field.dart';
+import 'package:gopeed/l10n/l10n.dart';
+import 'package:gopeed/shared/theme/app_component_themes.dart';
+import 'package:gopeed/shared/theme/app_theme.dart';
+import 'package:shadcn_flutter/shadcn_flutter.dart' as shad;
+
+void main() {
+  for (final platform in [TargetPlatform.android, TargetPlatform.iOS, TargetPlatform.macOS]) {
+    for (final scale in [1.0, 1.5, 2.0]) {
+      testWidgets('history hint and input line align on $platform at scale $scale', (tester) async {
+        debugDefaultTargetPlatformOverride = platform;
+        addTearDown(() => debugDefaultTargetPlatformOverride = null);
+        final controller = TextEditingController();
+        addTearDown(controller.dispose);
+        String? query;
+        for (final width in [280.0, 360.0, 600.0]) {
+          await tester.pumpWidget(
+            shad.ShadcnApp(
+              theme: AppTheme.light(),
+              materialTheme: AppTheme.materialLight(),
+              localizationsDelegates: AppLocalizations.localizationsDelegates,
+              supportedLocales: AppLocalizations.supportedLocales,
+              home: AppComponentThemes(
+                child: Builder(
+                  builder: (context) => Localizations.override(
+                    context: context,
+                    locale: const Locale('zh'),
+                    child: MediaQuery(
+                      data: MediaQueryData(textScaler: TextScaler.linear(scale)),
+                      child: Center(
+                        child: SizedBox(
+                          width: width,
+                          child: HistorySearchField(controller: controller, onChanged: (value) => query = value),
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              ),
+            ),
+          );
+          await tester.pumpAndSettle();
+          final editable = tester.state<EditableTextState>(find.byType(EditableText)).renderEditable;
+          final hint = tester.renderObject<RenderBox>(find.text('搜索历史记录…'));
+          expect(editable.preferredLineHeight, lessThanOrEqualTo(editable.size.height));
+          expect(hint.size.height, closeTo(editable.preferredLineHeight, 0.1));
+          expect(hint.localToGlobal(Offset.zero).dy, closeTo(editable.localToGlobal(Offset.zero).dy, 0.1));
+          expect(tester.takeException(), isNull);
+        }
+        await tester.enterText(find.byType(EditableText), 'example');
+        expect(query, 'example');
+        debugDefaultTargetPlatformOverride = null;
+      });
+    }
+  }
+}