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/routes/membership_routes.go

@@ -0,0 +1,17 @@
+package routes
+
+import (
+	"github.com/gin-gonic/gin"
+
+	membershiphandler "wx_service/internal/membership/handler"
+)
+
+func registerMembershipRoutes(protected *gin.RouterGroup, redeemCodeHandler *membershiphandler.RedeemCodeHandler) {
+	// 会员兑换码：生成（后台口令鉴权）+ 兑换（登录用户）
+	membership := protected.Group("/membership")
+	{
+		membership.POST("/redeem_codes", redeemCodeHandler.Generate)
+		membership.POST("/redeem", redeemCodeHandler.Redeem)
+	}
+}
+