feat: Add UiEmptyState widget and integrate it into BankAccountPage and WorkerHomePage for improved empty state handling

apps/mobile/packages/design_system/lib/design_system.dart

@@ -13,3 +13,4 @@ export 'src/widgets/ui_chip.dart';
 export 'src/widgets/ui_loading_page.dart';
 export 'src/widgets/ui_snackbar.dart';
 export 'src/widgets/ui_notice_banner.dart';
+export 'src/widgets/ui_empty_state.dart';

apps/mobile/packages/design_system/lib/src/ui_typography.dart

@@ -131,6 +131,15 @@ class UiTypography {
     color: UiColors.textPrimary,
   );
 
+  /// Title 1 Bold - Font: Instrument Sans, Size: 16, Height: 1.5 (#121826)
+  /// Used for section headers and important labels.
+  static final TextStyle title1b = _primaryBase.copyWith(
+    fontWeight: FontWeight.w600,
+    fontSize: 18,
+    height: 1.5,
+    color: UiColors.textPrimary,
+  );
+
   /// Title 2 Bold - Font: Instrument Sans, Size: 20, Height: 1.1 (#121826)
   static final TextStyle title2b = _primaryBase.copyWith(
     fontWeight: FontWeight.w600,

apps/mobile/packages/design_system/lib/src/widgets/ui_empty_state.dart

@@ -0,0 +1,44 @@
+import 'package:design_system/design_system.dart';
+import 'package:flutter/material.dart';
+
+class UiEmptyState extends StatelessWidget {
+  const UiEmptyState({
+    super.key,
+    required this.icon,
+    required this.title,
+    required this.description,
+    this.iconColor,
+  });
+
+  final IconData icon;
+  final String title;
+  final String description;
+  final Color? iconColor;
+
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: Column(
+        mainAxisAlignment: MainAxisAlignment.center,
+        children: <Widget>[
+          Icon(icon, size: 64, color: iconColor ?? UiColors.iconDisabled),
+          const SizedBox(height: UiConstants.space5),
+          Text(
+            title,
+            style: UiTypography.title1b.textDescription,
+            textAlign: TextAlign.center,
+          ),
+          const SizedBox(height: UiConstants.space1),
+          Padding(
+            padding: const EdgeInsets.symmetric(horizontal: UiConstants.space4),
+            child: Text(
+              description,
+              style: UiTypography.body2m.textDescription,
+              textAlign: TextAlign.center,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}