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.

docs/sql/smoke.sql

@@ -5,12 +5,52 @@ CREATE TABLE `fa_smoke_log` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
   `uid` int(11) NOT NULL COMMENT '用户ID',
   `smoke_time` date DEFAULT NULL COMMENT '抽烟时间',
+  `smoke_at` datetime DEFAULT NULL COMMENT '真实抽烟时间（可补录，精确到时分秒；为空则可用 createtime 近似）',
   `remark` text COMMENT '抽烟原因',
   `createtime` int(11) DEFAULT NULL COMMENT '创建时间',
   `updatetime` int(11) DEFAULT NULL COMMENT '修改时间',
   `deletetime` int(11) DEFAULT NULL COMMENT '删除时间',
   `level` bigint(2) DEFAULT '1' COMMENT '烟瘾程度',
   `num` int(2) DEFAULT '1' COMMENT '抽烟数量',
-  PRIMARY KEY (`id`,`uid`)
+  PRIMARY KEY (`id`,`uid`),
+  KEY `idx_smoke_uid_date` (`uid`,`smoke_time`),
+  KEY `idx_smoke_uid_at` (`uid`,`smoke_at`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='抽烟记录';
 
+-- AI 戒烟建议（按天缓存，避免重复调用；通常 date=昨天）
+-- 说明：
+-- - access gating：会员用户直接可用；非会员需要先完成“看广告解锁”（见 fa_smoke_ai_advice_unlocks）
+-- - input_snapshot：建议将“昨日总量 + 时间节点列表”作为 JSON 落库，便于追溯与复现
+CREATE TABLE IF NOT EXISTS `fa_smoke_ai_advice` (
+  `id` bigint unsigned NOT NULL AUTO_INCREMENT,
+  `uid` int(11) NOT NULL COMMENT '用户ID',
+  `advice_date` date NOT NULL COMMENT '建议针对的日期（通常=昨天）',
+  `prompt_version` varchar(30) NOT NULL DEFAULT 'v1' COMMENT '提示词版本',
+  `provider` varchar(30) DEFAULT NULL COMMENT 'AI 提供方（可选）',
+  `model` varchar(60) DEFAULT NULL COMMENT '模型名（可选）',
+  `input_snapshot` json NOT NULL COMMENT '当次输入快照（昨日总量+节点）',
+  `advice` mediumtext NOT NULL COMMENT 'AI 建议内容（文本/Markdown）',
+  `tokens_in` int DEFAULT NULL,
+  `tokens_out` int DEFAULT NULL,
+  `cost_cent` int DEFAULT NULL COMMENT '成本（分，可选）',
+  `createtime` int(11) DEFAULT NULL COMMENT '创建时间',
+  `updatetime` int(11) DEFAULT NULL COMMENT '修改时间',
+  `deletetime` int(11) DEFAULT NULL COMMENT '删除时间',
+  PRIMARY KEY (`id`),
+  UNIQUE KEY `uniq_smoke_ai_advice` (`uid`,`advice_date`,`prompt_version`),
+  KEY `idx_smoke_ai_advice_uid_date` (`uid`,`advice_date`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='每日AI戒烟建议';
+
+-- 每日广告解锁记录（非会员：当天/指定日期解锁后即可生成建议）
+CREATE TABLE IF NOT EXISTS `fa_smoke_ai_advice_unlocks` (
+  `id` bigint unsigned NOT NULL AUTO_INCREMENT,
+  `uid` int(11) NOT NULL COMMENT '用户ID',
+  `unlock_date` date NOT NULL COMMENT '解锁的建议日期（通常=昨天）',
+  `ad_watched_at` datetime NOT NULL COMMENT '完成观看时间',
+  `createtime` int(11) DEFAULT NULL COMMENT '创建时间',
+  `updatetime` int(11) DEFAULT NULL COMMENT '修改时间',
+  `deletetime` int(11) DEFAULT NULL COMMENT '删除时间',
+  PRIMARY KEY (`id`),
+  UNIQUE KEY `uniq_smoke_ai_unlock` (`uid`,`unlock_date`),
+  KEY `idx_smoke_ai_unlock_uid_date` (`uid`,`unlock_date`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='AI戒烟建议-广告解锁';