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/src/Application/Game/commands/GenerateBoardCommandHandler.ts

@@ -0,0 +1,63 @@
+import { GenerateBoardCommand } from './GenerateBoardCommand';
+import { BoardGenerationService } from '../BoardGenerationService';
+import { RedisService } from '../../Services/RedisService';
+import { logOther, logError } from '../../Services/Logger';
+import { BoardData } from '../../../Domain/Game/GameAggregate';
+
+export class GenerateBoardCommandHandler {
+    constructor(
+        private readonly boardGenerationService: BoardGenerationService,
+        private readonly redisService: RedisService
+    ) {}
+
+    async execute(cmd: GenerateBoardCommand): Promise<void> {
+        try {
+            logOther(`Starting board generation for game ${cmd.gameId}`);
+            const startTime = Date.now();
+
+            // Generate board with 20-30 rule validation
+            const boardData = await this.boardGenerationService.generateBoard(
+                cmd.positiveFieldCount,
+                cmd.negativeFieldCount,
+                cmd.luckFieldCount
+            );
+
+            // Store in Redis
+            const boardDataWithMetadata: BoardData = {
+                ...boardData,
+                gameId: cmd.gameId,
+                generatedAt: new Date(),
+                generationComplete: true
+            };
+
+            await this.redisService.setWithExpiry(
+                `game_board_${cmd.gameId}`,
+                JSON.stringify(boardDataWithMetadata),
+                24 * 60 * 60 // 24 hours
+            );
+
+            const executionTime = Date.now() - startTime;
+            logOther(`Board generation completed for game ${cmd.gameId} in ${executionTime}ms using pattern-based approach`);
+
+        } catch (error) {
+            logError(`Board generation failed for game ${cmd.gameId}:`, error as Error);
+            
+            // Store error state in Redis
+            const errorData: BoardData = {
+                gameId: cmd.gameId,
+                fields: [],
+                generationComplete: false,
+                error: error instanceof Error ? error.message : 'Unknown error',
+                generatedAt: new Date()
+            };
+
+            await this.redisService.setWithExpiry(
+                `game_board_${cmd.gameId}`,
+                JSON.stringify(errorData),
+                24 * 60 * 60
+            );
+            
+            throw error;
+        }
+    }
+}