feat(product): 实现产品需求管理模块（后端 + 前端）

后端：Product Module（CRUD）、Requirement Module（CRUD + 状态机流转）、PrismaService
前端：产品列表页、产品详情页（含需求池 Tab）、Zustand Store、API 封装

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/server/src/modules/requirement/requirement.module.ts

@@ -0,0 +1,10 @@
+import { Module } from '@nestjs/common';
+import { RequirementController } from './requirement.controller';
+import { RequirementService } from './requirement.service';
+
+@Module({
+  controllers: [RequirementController],
+  providers: [RequirementService],
+  exports: [RequirementService],
+})
+export class RequirementModule {}