feat: 智能客服系统基础架构完成

✅ 已完成功能：
1. 项目基础设施和Docker开发环境
2. 前端React 18 + TypeScript架构
3. 后端Golang + Gin框架
4. 多租户数据库设计
5. 完整API路由系统
6. 智能客服聊天界面
7. 详细文档和部署指南

🔧 技术栈：
- 前端：React 18, TypeScript, Vite, Zustand
- 后端：Golang, Gin, GORM, PostgreSQL
- 部署：Docker, Docker Compose

🎨 设计规范：
- 无渐变色，无紫色
- 简洁专业的中性色系
- 响应式布局

📊 状态：
- 前端开发服务器：http://localhost:5173
- 后端API服务：http://localhost:8080
- 数据库：PostgreSQL + Redis
- 完整的多租户架构

作者：小弟 (大哥的AI助手)
日期：2026-02-27

backend/config/config.go

@@ -0,0 +1,123 @@
+package config
+
+import (
+	"os"
+	"strconv"
+)
+
+type Config struct {
+	Server   ServerConfig
+	Database DatabaseConfig
+	Redis    RedisConfig
+	JWT      JWTConfig
+	AI       AIConfig
+	WebSocket WebSocketConfig
+}
+
+type ServerConfig struct {
+	Port         int
+	Mode         string
+	ReadTimeout  int
+	WriteTimeout int
+}
+
+type DatabaseConfig struct {
+	Host     string
+	Port     int
+	User     string
+	Password string
+	DBName   string
+	SSLMode  string
+}
+
+type RedisConfig struct {
+	Host     string
+	Port     int
+	Password string
+	DB       int
+}
+
+type JWTConfig struct {
+	Secret     string
+	Expiration int
+}
+
+type AIConfig struct {
+	Provider   string
+	APIKey     string
+	Model      string
+	BaseURL    string
+	MaxTokens  int
+	Temperature float64
+}
+
+type WebSocketConfig struct {
+	Port int
+	Path string
+}
+
+func Load() (*Config, error) {
+	return &Config{
+		Server: ServerConfig{
+			Port:         getEnvAsInt("SERVER_PORT", 8080),
+			Mode:         getEnv("SERVER_MODE", "debug"),
+			ReadTimeout:  getEnvAsInt("SERVER_READ_TIMEOUT", 30),
+			WriteTimeout: getEnvAsInt("SERVER_WRITE_TIMEOUT", 30),
+		},
+		Database: DatabaseConfig{
+			Host:     getEnv("DB_HOST", "localhost"),
+			Port:     getEnvAsInt("DB_PORT", 5432),
+			User:     getEnv("DB_USER", "postgres"),
+			Password: getEnv("DB_PASSWORD", "postgres"),
+			DBName:   getEnv("DB_NAME", "customer_service"),
+			SSLMode:  getEnv("DB_SSL_MODE", "disable"),
+		},
+		Redis: RedisConfig{
+			Host:     getEnv("REDIS_HOST", "localhost"),
+			Port:     getEnvAsInt("REDIS_PORT", 6379),
+			Password: getEnv("REDIS_PASSWORD", ""),
+			DB:       getEnvAsInt("REDIS_DB", 0),
+		},
+		JWT: JWTConfig{
+			Secret:     getEnv("JWT_SECRET", "your-secret-key-change-in-production"),
+			Expiration: getEnvAsInt("JWT_EXPIRATION", 86400),
+		},
+		AI: AIConfig{
+			Provider:   getEnv("AI_PROVIDER", "openai"),
+			APIKey:     getEnv("AI_API_KEY", ""),
+			Model:      getEnv("AI_MODEL", "gpt-3.5-turbo"),
+			BaseURL:    getEnv("AI_BASE_URL", "https://api.openai.com/v1"),
+			MaxTokens:  getEnvAsInt("AI_MAX_TOKENS", 1000),
+			Temperature: getEnvAsFloat("AI_TEMPERATURE", 0.7),
+		},
+		WebSocket: WebSocketConfig{
+			Port: getEnvAsInt("WS_PORT", 8081),
+			Path: getEnv("WS_PATH", "/ws"),
+		},
+	}, nil
+}
+
+func getEnv(key, defaultValue string) string {
+	if value := os.Getenv(key); value != "" {
+		return value
+	}
+	return defaultValue
+}
+
+func getEnvAsInt(key string, defaultValue int) int {
+	if value := os.Getenv(key); value != "" {
+		if intValue, err := strconv.Atoi(value); err == nil {
+			return intValue
+		}
+	}
+	return defaultValue
+}
+
+func getEnvAsFloat(key string, defaultValue float64) float64 {
+	if value := os.Getenv(key); value != "" {
+		if floatValue, err := strconv.ParseFloat(value, 64); err == nil {
+			return floatValue
+		}
+	}
+	return defaultValue
+}