refactor: 重构项目目录与代码结构，清理冗余文件

本次提交进行了大规模的项目结构调整：
1. 调整文件目录归属，将模块代码按功能域重新组织
2. 删除多处冗余的DTO、实体类和模块文件
3. 统一了常量、装饰器、工具类的存放位置
4. 修复了`.gitignore`的日志目录匹配规则
5. 新增了健康检查、认证、用户、剧集、订单等核心业务模块

decorators/api-message.decorator.ts

@@ -0,0 +1,6 @@
+import { SetMetadata } from '@nestjs/common';
+
+export const API_MESSAGE_METADATA = 'api:message';
+
+export const ApiMessage = (message: string) =>
+  SetMetadata(API_MESSAGE_METADATA, message);

decorators/current-admin.decorator.ts

@@ -0,0 +1,12 @@
+import { createParamDecorator, ExecutionContext } from '@nestjs/common';
+import { Request } from 'express';
+import { AdminUserRecord } from '../interfaces/admin-records.interface';
+
+export const CurrentAdmin = createParamDecorator(
+  (_data: unknown, ctx: ExecutionContext): AdminUserRecord | undefined => {
+    const request = ctx
+      .switchToHttp()
+      .getRequest<Request & { adminUser?: AdminUserRecord }>();
+    return request.adminUser;
+  },
+);

decorators/current-user.decorator.ts

@@ -0,0 +1,10 @@
+import { createParamDecorator, ExecutionContext } from '@nestjs/common';
+import { Request } from 'express';
+import { UserRecord } from '../../users/interfaces/user-record.interface';
+
+export const CurrentUser = createParamDecorator(
+  (_data: unknown, ctx: ExecutionContext): UserRecord | undefined => {
+    const request = ctx.switchToHttp().getRequest<Request & { user?: UserRecord }>();
+    return request.user;
+  },
+);

decorators/require-permissions.decorator.ts

@@ -0,0 +1,6 @@
+import { SetMetadata } from '@nestjs/common';
+
+export const REQUIRED_PERMISSIONS_METADATA = 'admin:required-permissions';
+
+export const RequirePermissions = (...permissions: string[]) =>
+  SetMetadata(REQUIRED_PERMISSIONS_METADATA, permissions);