Add Docker support and enhance data models for tender details

- Introduced a .dockerignore file to optimize Docker builds by excluding unnecessary files.
- Updated the Dockerfile to use a Flutter base image, enabling web builds for the application.
- Added new data models for `Lot` and `OrganizationAddress` to represent tender details more accurately.
- Enhanced the `Organization` model to include `companyId` and a nested `address` field.
- Updated the `TenderData` model to include new fields such as `noticeTypeCode`, `formType`, and `lots`, reflecting the API response structure.
- Regenerated necessary code for data models to ensure compatibility with the updated structures.

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

@@ -0,0 +1,19 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'lot.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+_Lot _$LotFromJson(Map<String, dynamic> json) => _Lot(
+  lotId: json['lot_id'] as String?,
+  title: json['title'] as String?,
+  description: json['description'] as String?,
+);
+
+Map<String, dynamic> _$LotToJson(_Lot instance) => <String, dynamic>{
+  'lot_id': instance.lotId,
+  'title': instance.title,
+  'description': instance.description,
+};