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/common/redis/cache/session_user_cache.go

@@ -0,0 +1,72 @@
+package cache
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+
+	"wx_service/internal/model"
+)
+
+type SessionUserCache struct {
+	rc        *redis.Client
+	keyPrefix string
+	ttl       time.Duration
+}
+
+func NewSessionUserCache(rc *redis.Client, keyPrefix string, ttl time.Duration) *SessionUserCache {
+	return &SessionUserCache{
+		rc:        rc,
+		keyPrefix: keyPrefix,
+		ttl:       ttl,
+	}
+}
+
+func (c *SessionUserCache) Get(ctx context.Context, token string) (*model.User, bool, error) {
+	if c == nil || c.rc == nil || token == "" {
+		return nil, false, nil
+	}
+	key := c.sessionKey(token)
+	val, err := c.rc.Get(ctx, key).Bytes()
+	if err != nil {
+		if errors.Is(err, redis.Nil) {
+			return nil, false, nil
+		}
+		return nil, false, fmt.Errorf("redis get: %w", err)
+	}
+
+	var user model.User
+	if err := json.Unmarshal(val, &user); err != nil {
+		_ = c.rc.Del(ctx, key).Err()
+		return nil, false, nil
+	}
+	return &user, true, nil
+}
+
+func (c *SessionUserCache) Set(ctx context.Context, token string, user *model.User) error {
+	if c == nil || c.rc == nil || token == "" || user == nil {
+		return nil
+	}
+	key := c.sessionKey(token)
+	body, err := json.Marshal(user)
+	if err != nil {
+		return fmt.Errorf("marshal user: %w", err)
+	}
+	if err := c.rc.Set(ctx, key, body, c.ttl).Err(); err != nil {
+		return fmt.Errorf("redis set: %w", err)
+	}
+	return nil
+}
+
+func (c *SessionUserCache) sessionKey(token string) string {
+	prefix := c.keyPrefix
+	if prefix != "" && !strings.HasSuffix(prefix, ":") {
+		prefix += ":"
+	}
+	return prefix + "session_user:" + token
+}

internal/common/redis/service/client.go

@@ -0,0 +1,58 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+
+	"wx_service/config"
+)
+
+type Client struct {
+	rc         *redis.Client
+	keyPrefix  string
+	sessionTTL time.Duration
+}
+
+func NewClient(cfg config.RedisConfig) (*Client, error) {
+	if cfg.Addr == "" {
+		return nil, nil
+	}
+
+	rc := redis.NewClient(&redis.Options{
+		Addr:     cfg.Addr,
+		Password: cfg.Password,
+		DB:       cfg.DB,
+	})
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+	defer cancel()
+	if err := rc.Ping(ctx).Err(); err != nil {
+		return nil, fmt.Errorf("ping redis: %w", err)
+	}
+
+	ttlSeconds := cfg.SessionTTLSeconds
+	if ttlSeconds <= 0 {
+		ttlSeconds = 86400
+	}
+
+	return &Client{
+		rc:         rc,
+		keyPrefix:  cfg.KeyPrefix,
+		sessionTTL: time.Duration(ttlSeconds) * time.Second,
+	}, nil
+}
+
+func (c *Client) Redis() *redis.Client {
+	return c.rc
+}
+
+func (c *Client) KeyPrefix() string {
+	return c.keyPrefix
+}
+
+func (c *Client) SessionTTL() time.Duration {
+	return c.sessionTTL
+}