新增AI教练模块，包括控制器、服务、模型及数据传输对象，更新应用模块以引入新模块，同时在打卡模块中添加按时间范围返回每日打卡状态的功能

src/ai-coach/ai-coach.module.ts

@@ -0,0 +1,19 @@
+import { Module } from '@nestjs/common';
+import { SequelizeModule } from '@nestjs/sequelize';
+import { ConfigModule } from '@nestjs/config';
+import { AiCoachController } from './ai-coach.controller';
+import { AiCoachService } from './ai-coach.service';
+import { AiMessage } from './models/ai-message.model';
+import { UsersModule } from '../users/users.module';
+
+@Module({
+  imports: [
+    ConfigModule,
+    UsersModule,
+    SequelizeModule.forFeature([AiMessage]),
+  ],
+  controllers: [AiCoachController],
+  providers: [AiCoachService],
+})
+export class AiCoachModule { }
+