feat: 添加 AI 推荐功能

新增 AI 推荐模块，包括前端界面和后端服务
添加 OpenAI API 密钥配置
实现工程数据分析和推荐功能

src/ai/ai.controller.ts

@@ -0,0 +1,23 @@
+import { Controller, Post, Body } from '@nestjs/common';
+import { AiService } from './ai.service';
+
+export class BidDataDto {
+  title: string;
+  url: string;
+  source: string;
+  publishDate: string;
+}
+
+export class BidsRequestDto {
+  bids: BidDataDto[];
+}
+
+@Controller('api/ai')
+export class AiController {
+  constructor(private readonly aiService: AiService) {}
+
+  @Post('recommendations')
+  async getRecommendations(@Body() request: BidsRequestDto) {
+    return this.aiService.getRecommendations(request.bids);
+  }
+}

src/ai/ai.module.ts

@@ -0,0 +1,12 @@
+import { Module } from '@nestjs/common';
+import { ConfigModule } from '@nestjs/config';
+import { AiController } from './ai.controller';
+import { AiService } from './ai.service';
+
+@Module({
+  imports: [ConfigModule],
+  controllers: [AiController],
+  providers: [AiService],
+  exports: [AiService],
+})
+export class AiModule {}