Enhance AI and Redis integration for smoke logging features

- Added AI configuration options to .env.example and config.go for OpenAI integration.
- Implemented Redis caching for session management in main.go and auth middleware.
- Updated smoke logging service to support real smoking time (`smoke_at`) and AI advice retrieval.
- Enhanced API routes to include endpoints for AI advice and unlock functionality for non-members.
- Improved database schema with new tables for AI advice and unlock records.
- Expanded documentation to cover new AI features and Redis caching implementation.

internal/middleware/auth_middleware.go

@@ -7,15 +7,17 @@ import (
 	"github.com/gin-gonic/gin"
 	"gorm.io/gorm"
 
+	rediscache "wx_service/internal/common/redis/cache"
 	"wx_service/internal/model"
 )
 
 const ContextCurrentUserKey = "currentUser"
 
-func AuthMiddleware(db *gorm.DB) gin.HandlerFunc {
+func AuthMiddleware(db *gorm.DB, sessionCache *rediscache.SessionUserCache) gin.HandlerFunc {
 	// AuthMiddleware 是一个 Gin 中间件：
 	// - 从 Authorization: Bearer <token> 里取 token
 	// - 用 token（这里是 session_key）查用户
+	// - (可选) 优先从 Redis 缓存读取，减少每次都访问数据库
 	// - 查到后放进 gin.Context，供后面的 handler 使用
 	return func(c *gin.Context) {
 		token := extractToken(c.GetHeader("Authorization"))
@@ -24,6 +26,14 @@ func AuthMiddleware(db *gorm.DB) gin.HandlerFunc {
 			return
 		}
 
+		if sessionCache != nil {
+			if cachedUser, ok, err := sessionCache.Get(c.Request.Context(), token); err == nil && ok && cachedUser != nil {
+				c.Set(ContextCurrentUserKey, cachedUser)
+				c.Next()
+				return
+			}
+		}
+
 		var user model.User
 		if err := db.WithContext(c.Request.Context()).Where("session_key = ?", token).First(&user).Error; err != nil {
 			if err == gorm.ErrRecordNotFound {
@@ -34,6 +44,10 @@ func AuthMiddleware(db *gorm.DB) gin.HandlerFunc {
 			return
 		}
 
+		if sessionCache != nil {
+			_ = sessionCache.Set(c.Request.Context(), token, &user)
+		}
+
 		c.Set(ContextCurrentUserKey, &user)
 		c.Next()
 	}