Added Tests for the overlay_widget_test.dart

Author: Tilakraj-B

test/widgets/overlay_widget_test.dart

@@ -0,0 +1,58 @@
+import 'package:apidash/consts.dart';
+import 'package:apidash/widgets/overlay_widget.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:lottie/lottie.dart';
+
+void main() {
+  testWidgets('OverlayWidgetTemplate Test', (WidgetTester tester) async {
+    late OverlayWidgetTemplate overlayWidget;
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Builder(
+          builder: (BuildContext context) {
+            overlayWidget = OverlayWidgetTemplate(context: context);
+            return Container(); // Return any widget here, as OverlayWidgetTemplate doesn't return a widget
+          },
+        ),
+      ),
+    );
+
+    overlayWidget.show(widget: const Text('Test'));
+    await tester.pump();
+    expect(find.text('Test'), findsOneWidget);
+
+    overlayWidget.hide();
+    await tester.pump();
+    expect(find.text('Test'), findsNothing);
+  });
+
+  testWidgets('SavingOverlay Test', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const MaterialApp(
+        home: Scaffold(
+          body: SavingOverlay(),
+        ),
+      ),
+    );
+
+    expect(find.byType(Card), findsOneWidget);
+    expect(find.byType(Lottie), findsOneWidget);
+    expect(find.text(kLabelSaving), findsOneWidget);
+  });
+
+  testWidgets('CompletedOverlay Test', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const MaterialApp(
+        home: Scaffold(
+          body: CompletedOverlay(),
+        ),
+      ),
+    );
+
+    expect(find.byType(Card), findsOneWidget);
+    expect(find.byType(Lottie), findsOneWidget);
+    expect(find.text(kLabelSaved), findsOneWidget);
+  });
+}