Add board service and repository, update routes and assets

- Introduced BoardService and BoardRepository for managing board-related data.
- Updated app routes to reflect the new board screen structure.
- Added new board-related assets to the asset manager.
- Refactored BoardScreen navigation to utilize the new provider structure.

lib/data/services/model/board_response/board_response.g.dart

@@ -0,0 +1,51 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'board_response.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+_BoardResponse _$BoardResponseFromJson(Map<String, dynamic> json) =>
+    _BoardResponse(
+      success: json['success'] as bool?,
+      message: json['message'] as String?,
+      data:
+          (json['data'] as List<dynamic>?)
+              ?.map((e) => BoardData.fromJson(e as Map<String, dynamic>))
+              .toList(),
+      error:
+          json['error'] == null
+              ? null
+              : ErrorModel.fromJson(json['error'] as Map<String, dynamic>),
+    );
+
+Map<String, dynamic> _$BoardResponseToJson(_BoardResponse instance) =>
+    <String, dynamic>{
+      'success': instance.success,
+      'message': instance.message,
+      'data': instance.data,
+      'error': instance.error,
+    };
+
+_BoardData _$BoardDataFromJson(Map<String, dynamic> json) => _BoardData(
+  id: json['id'] as String?,
+  description: json['description'] as String?,
+  deadline:
+      json['deadline'] == null
+          ? null
+          : DateTime.parse(json['deadline'] as String),
+  assignedTo: json['assignedTo'] as String?,
+  isReady: json['isReady'] as bool?,
+  status: json['status'] as String?,
+);
+
+Map<String, dynamic> _$BoardDataToJson(_BoardData instance) =>
+    <String, dynamic>{
+      'id': instance.id,
+      'description': instance.description,
+      'deadline': instance.deadline?.toIso8601String(),
+      'assignedTo': instance.assignedTo,
+      'isReady': instance.isReady,
+      'status': instance.status,
+    };