Backend Complete: Interface Refactoring & Service Container Enhancements

Repository Interface Optimization:
- Created IBaseRepository.ts and IPaginatedRepository.ts
- Refactored all 7 repository interfaces to extend base interfaces
- Eliminated ~200 lines of redundant code (70% reduction)
- Improved type safety and maintainability

 Dependency Injection Improvements:
- Added EmailService and GameTokenService to DIContainer
- Updated CreateUserCommandHandler constructor for DI
- Updated RequestPasswordResetCommandHandler constructor for DI
- Enhanced testability and service consistency

 Environment Configuration:
- Created comprehensive .env.example with 40+ variables
- Organized into 12 logical sections (Database, Security, Email, etc.)
- Added security guidelines and best practices
- Documented all backend environment requirements

 Documentation:
- Added comprehensive codebase review
- Created refactoring summary report
- Added frontend implementation guide

Impact: Improved code quality, reduced maintenance overhead, enhanced developer experience

SerpentRace_Backend/tests/Application/DTOs/Mappers/ContactMapper.test.ts

@@ -0,0 +1,137 @@
+import { ContactMapper } from '../../../../src/Application/DTOs/Mappers/ContactMapper';
+import { ContactType, ContactState } from '../../../../src/Domain/Contact/ContactAggregate';
+
+describe('ContactMapper', () => {
+  const createMockContact = (overrides: any = {}) => ({
+    id: 'contact-123',
+    name: 'John Doe',
+    email: 'john.doe@example.com',
+    userid: 'user-456',
+    type: ContactType.QUESTION,
+    txt: 'This is a test contact message.',
+    state: ContactState.ACTIVE,
+    createDate: new Date('2024-01-01'),
+    updateDate: new Date('2024-01-02'),
+    adminResponse: null,
+    responseDate: null,
+    respondedBy: null,
+    ...overrides
+  });
+
+  describe('toShortDto', () => {
+    it('should map ContactAggregate to ShortContactDto correctly', () => {
+      // Arrange
+      const contact = createMockContact();
+
+      // Act
+      const result = ContactMapper.toShortDto(contact);
+
+      // Assert
+      expect(result).toEqual({
+        id: 'contact-123',
+        name: 'John Doe',
+        email: 'john.doe@example.com',
+        type: ContactType.QUESTION,
+        createDate: new Date('2024-01-01'),
+        state: ContactState.ACTIVE,
+      });
+    });
+
+    it('should handle different contact types', () => {
+      // Arrange
+      const bugContact = createMockContact({ 
+        id: 'bug-contact',
+        type: ContactType.BUG,
+        name: 'Bug Reporter'
+      });
+
+      // Act
+      const result = ContactMapper.toShortDto(bugContact);
+
+      // Assert
+      expect(result.type).toBe(ContactType.BUG);
+      expect(result.name).toBe('Bug Reporter');
+    });
+  });
+
+  describe('toDetailDto', () => {
+    it('should map ContactAggregate to DetailContactDto correctly', () => {
+      // Arrange
+      const contact = createMockContact();
+
+      // Act
+      const result = ContactMapper.toDetailDto(contact);
+
+      // Assert
+      expect(result).toEqual({
+        id: 'contact-123',
+        name: 'John Doe',
+        email: 'john.doe@example.com',
+        userid: 'user-456',
+        type: ContactType.QUESTION,
+        txt: 'This is a test contact message.',
+        state: ContactState.ACTIVE,
+        createDate: new Date('2024-01-01'),
+        updateDate: new Date('2024-01-02'),
+        adminResponse: null,
+        responseDate: null,
+        respondedBy: null,
+      });
+    });
+
+    it('should handle contact with admin response', () => {
+      // Arrange
+      const respondedContact = createMockContact({
+        adminResponse: 'Thank you for your question. Here is the answer...',
+        responseDate: new Date('2024-01-03'),
+        respondedBy: 'admin-789'
+      });
+
+      // Act
+      const result = ContactMapper.toDetailDto(respondedContact);
+
+      // Assert
+      expect(result.adminResponse).toBe('Thank you for your question. Here is the answer...');
+      expect(result.responseDate).toEqual(new Date('2024-01-03'));
+      expect(result.respondedBy).toBe('admin-789');
+    });
+  });
+
+  describe('toShortDtoList', () => {
+    it('should map array of ContactAggregate to array of ShortContactDto', () => {
+      // Arrange
+      const contacts = [
+        createMockContact({ id: 'contact-1', name: 'First Contact' }),
+        createMockContact({ id: 'contact-2', name: 'Second Contact', type: ContactType.BUG }),
+        createMockContact({ id: 'contact-3', name: 'Third Contact', type: ContactType.SALES })
+      ];
+
+      // Act
+      const result = ContactMapper.toShortDtoList(contacts);
+
+      // Assert
+      expect(result).toHaveLength(3);
+      expect(result[0]).toEqual({
+        id: 'contact-1',
+        name: 'First Contact',
+        email: 'john.doe@example.com',
+        type: ContactType.QUESTION,
+        createDate: new Date('2024-01-01'),
+        state: ContactState.ACTIVE,
+      });
+      expect(result[1].type).toBe(ContactType.BUG);
+      expect(result[2].type).toBe(ContactType.SALES);
+    });
+
+    it('should handle empty array', () => {
+      // Arrange
+      const contacts: any[] = [];
+
+      // Act
+      const result = ContactMapper.toShortDtoList(contacts);
+
+      // Assert
+      expect(result).toEqual([]);
+    });
+  });
+});