feat: 重构多语言模块，符合NestJS规范

- 重构LanguageUtils为LanguageService，实现ILanguageService接口
- 移除自定义验证管道和装饰器，使用标准NestJS验证
- 集成框架ValidatorService进行业务验证
- 简化目录结构，移除不必要的子目录
- 支持模块化语言包加载（common、user、order等）
- 统一API响应格式（code、msg、data、timestamp）
- 添加ValidationExceptionFilter处理多语言验证错误
- 完善多语言示例和文档

tools/generators/base-generator.js

@@ -0,0 +1,184 @@
+#!/usr/bin/env node
+
+const fs = require('fs');
+const path = require('path');
+
+/**
+ * 基础生成器类
+ * 提供通用的 dry-run、文件操作、日志等功能
+ */
+class BaseGenerator {
+  constructor(generatorName = 'Generator') {
+    this.generatorName = generatorName;
+    
+    // 从环境变量或参数读取配置
+    this.dryRun = process.env.DRY_RUN === 'true' || process.argv.includes('--dry-run');
+    this.verbose = process.env.VERBOSE === 'true' || process.argv.includes('--verbose');
+    
+    this.stats = {
+      filesCreated: 0,
+      filesUpdated: 0,
+      filesSkipped: 0,
+      errors: 0
+    };
+  }
+
+  /**
+   * 安全写入文件（支持 dry-run）
+   */
+  writeFile(filePath, content, description = '') {
+    try {
+      if (this.dryRun) {
+        console.log(`   [DRY-RUN] Would create/update: ${filePath}`);
+        if (this.verbose && description) {
+          console.log(`             Description: ${description}`);
+        }
+        this.stats.filesCreated++;
+        return true;
+      }
+
+      // 确保目录存在
+      this.ensureDir(path.dirname(filePath));
+      
+      // 写入文件
+      fs.writeFileSync(filePath, content, 'utf8');
+      
+      const action = fs.existsSync(filePath) ? 'Updated' : 'Created';
+      console.log(`     ✅ ${action}: ${filePath}`);
+      
+      if (action === 'Created') {
+        this.stats.filesCreated++;
+      } else {
+        this.stats.filesUpdated++;
+      }
+      
+      return true;
+    } catch (error) {
+      console.error(`     ❌ Failed to write ${filePath}:`, error.message);
+      this.stats.errors++;
+      return false;
+    }
+  }
+
+  /**
+   * 确保目录存在
+   */
+  ensureDir(dirPath) {
+    if (this.dryRun) {
+      return;
+    }
+    
+    if (!fs.existsSync(dirPath)) {
+      fs.mkdirSync(dirPath, { recursive: true });
+    }
+  }
+
+  /**
+   * 读取文件（安全）
+   */
+  readFile(filePath) {
+    try {
+      if (!fs.existsSync(filePath)) {
+        return null;
+      }
+      return fs.readFileSync(filePath, 'utf8');
+    } catch (error) {
+      console.error(`     ❌ Failed to read ${filePath}:`, error.message);
+      return null;
+    }
+  }
+
+  /**
+   * 检查文件是否存在
+   */
+  fileExists(filePath) {
+    return fs.existsSync(filePath);
+  }
+
+  /**
+   * 日志输出
+   */
+  log(message, level = 'info') {
+    const prefix = {
+      'info': '   ℹ️ ',
+      'success': '   ✅',
+      'warning': '   ⚠️ ',
+      'error': '   ❌',
+      'debug': '   🔍'
+    };
+    
+    if (level === 'debug' && !this.verbose) {
+      return;
+    }
+    
+    console.log(`${prefix[level] || '   '}${message}`);
+  }
+
+  /**
+   * 输出统计信息
+   */
+  printStats(additionalStats = {}) {
+    console.log('\n📊 Generation Statistics');
+    console.log('==================================================');
+    
+    if (this.dryRun) {
+      console.log('   🔍 DRY-RUN MODE - No files were actually modified');
+    }
+    
+    console.log(`   📁 Files Created: ${this.stats.filesCreated}`);
+    console.log(`   🔄 Files Updated: ${this.stats.filesUpdated}`);
+    console.log(`   ⏭️  Files Skipped: ${this.stats.filesSkipped}`);
+    console.log(`   ❌ Errors: ${this.stats.errors}`);
+    
+    // 输出额外的统计信息
+    for (const [key, value] of Object.entries(additionalStats)) {
+      console.log(`   📈 ${key}: ${value}`);
+    }
+    
+    const total = this.stats.filesCreated + this.stats.filesUpdated;
+    const successRate = total > 0 
+      ? ((total / (total + this.stats.errors)) * 100).toFixed(2) 
+      : '0.00';
+    
+    console.log(`   📊 Success Rate: ${successRate}%`);
+    console.log('==================================================');
+  }
+
+  /**
+   * kebab-case 转换
+   */
+  toKebabCase(str) {
+    return String(str)
+      .replace(/([a-z0-9])([A-Z])/g, '$1-$2')
+      .replace(/_/g, '-')
+      .toLowerCase();
+  }
+
+  /**
+   * PascalCase 转换
+   */
+  toPascalCase(str) {
+    return String(str)
+      .split(/[-_]/)
+      .map(word => word.charAt(0).toUpperCase() + word.slice(1))
+      .join('');
+  }
+
+  /**
+   * camelCase 转换
+   */
+  toCamelCase(str) {
+    const pascal = this.toPascalCase(str);
+    return pascal.charAt(0).toLowerCase() + pascal.slice(1);
+  }
+
+  /**
+   * snake_case 转换
+   */
+  toSnakeCase(str) {
+    return str.replace(/([A-Z])/g, '_$1').toLowerCase().replace(/^_/, '');
+  }
+}
+
+module.exports = BaseGenerator;
+