feat: 初始化微信小程序后端骨架

- NestJS + TypeScript + Prisma + PostgreSQL 工程骨架
- 微信登录安全流程：服务端 code2Session 换 openid 后签发 JWT，
  session_key 缓存于 Redis，不信任前端 openid
- 统一响应/异常处理、JWT 全局鉴权（@Public 豁免）、Swagger 文档
- Prisma 全量核心 schema（用户/分类/商品/设计清单/地址/订单/支付/上传/定制任务）+ seed
- 业务模块空壳（商品/分类/设计清单/地址/订单/支付/上传/BullMQ 队列）
- Docker 多阶段镜像 + 本地/生产 docker-compose
- docs：密钥获取指南、COS SDK 移除记录

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/app.module.ts

@@ -0,0 +1,49 @@
+import { Module } from '@nestjs/common';
+import { ConfigModule } from '@nestjs/config';
+import { APP_GUARD } from '@nestjs/core';
+import { validationSchema } from './config/validation.schema';
+import { PrismaModule } from './prisma/prisma.module';
+import { RedisModule } from './redis/redis.module';
+import { JwtAuthGuard } from './common/guards/jwt-auth.guard';
+
+import { WechatModule } from './wechat/wechat.module';
+import { AuthModule } from './auth/auth.module';
+import { UsersModule } from './users/users.module';
+import { ProductsModule } from './products/products.module';
+import { CategoriesModule } from './categories/categories.module';
+import { DesignListModule } from './design-list/design-list.module';
+import { AddressesModule } from './addresses/addresses.module';
+import { OrdersModule } from './orders/orders.module';
+import { PaymentsModule } from './payments/payments.module';
+import { UploadModule } from './upload/upload.module';
+import { QueueModule } from './queue/queue.module';
+import { HealthModule } from './health/health.module';
+
+@Module({
+  imports: [
+    ConfigModule.forRoot({
+      isGlobal: true,
+      // 直接读 env（已在 .env / 容器环境注入），用 configuration() 分组
+      load: [() => require('./config/configuration').default()],
+      validationSchema,
+      validationOptions: { abortEarly: false },
+    }),
+    PrismaModule,
+    RedisModule,
+    WechatModule,
+    AuthModule,
+    UsersModule,
+    ProductsModule,
+    CategoriesModule,
+    DesignListModule,
+    AddressesModule,
+    OrdersModule,
+    PaymentsModule,
+    UploadModule,
+    QueueModule,
+    HealthModule,
+  ],
+  // 默认全局开启 JWT 鉴权，@Public() 路由除外
+  providers: [{ provide: APP_GUARD, useClass: JwtAuthGuard }],
+})
+export class AppModule {}