重构 API 为 8 领域 + 应用层架构

将后端模块拆分为 domains、applications、shared 三层，结算计算器移入 domain 纯函数目录，API 路径与测试保持不变。

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/api/src/shared/common/decorators.ts

@@ -0,0 +1,48 @@
+import { createParamDecorator, ExecutionContext, SetMetadata } from '@nestjs/common';
+
+export const IS_PUBLIC_KEY = 'isPublic';
+export const Public = () => SetMetadata(IS_PUBLIC_KEY, true);
+
+export const PERMISSIONS_KEY = 'permissions';
+export const RequirePermissions = (...permissions: string[]) =>
+  SetMetadata(PERMISSIONS_KEY, permissions);
+
+export const CurrentUser = createParamDecorator(
+  (data: string | undefined, ctx: ExecutionContext) => {
+    const request = ctx.switchToHttp().getRequest();
+    const user = request.user;
+    return data ? user?.[data] : user;
+  },
+);
+
+export function generateBetNo(): string {
+  const ts = Date.now().toString(36).toUpperCase();
+  const rand = Math.random().toString(36).substring(2, 8).toUpperCase();
+  return `BET${ts}${rand}`;
+}
+
+export function generateTransactionId(): string {
+  const ts = Date.now().toString(36).toUpperCase();
+  const rand = Math.random().toString(36).substring(2, 8).toUpperCase();
+  return `TXN${ts}${rand}`;
+}
+
+export function generateBatchNo(prefix: string): string {
+  const ts = Date.now().toString(36).toUpperCase();
+  return `${prefix}${ts}`;
+}
+
+export function serializeBigInt(obj: unknown): unknown {
+  if (obj === null || obj === undefined) return obj;
+  if (typeof obj === 'bigint') return obj.toString();
+  if (obj instanceof Date) return obj.toISOString();
+  if (Array.isArray(obj)) return obj.map(serializeBigInt);
+  if (typeof obj === 'object') {
+    const result: Record<string, unknown> = {};
+    for (const [key, value] of Object.entries(obj as Record<string, unknown>)) {
+      result[key] = serializeBigInt(value);
+    }
+    return result;
+  }
+  return obj;
+}

apps/api/src/shared/common/filters.ts

@@ -0,0 +1,42 @@
+import {
+  ExceptionFilter,
+  Catch,
+  ArgumentsHost,
+  HttpException,
+  HttpStatus,
+} from '@nestjs/common';
+import { Response } from 'express';
+import { serializeBigInt } from './decorators';
+
+@Catch()
+export class GlobalExceptionFilter implements ExceptionFilter {
+  catch(exception: unknown, host: ArgumentsHost) {
+    const ctx = host.switchToHttp();
+    const response = ctx.getResponse<Response>();
+
+    let status = HttpStatus.INTERNAL_SERVER_ERROR;
+    let message = 'Internal server error';
+
+    if (exception instanceof HttpException) {
+      status = exception.getStatus();
+      const res = exception.getResponse();
+      message = typeof res === 'string' ? res : (res as { message?: string }).message || message;
+    } else if (exception instanceof Error) {
+      message = exception.message;
+    }
+
+    response.status(status).json({
+      success: false,
+      error: message,
+      data: null,
+    });
+  }
+}
+
+export function jsonResponse<T>(data: T, message?: string) {
+  return {
+    success: true,
+    data: serializeBigInt(data),
+    message,
+  };
+}