feat: Complete NestJS backend scaffold — 22 modules, 39 entities, WebSocket gateway

Full backend rewrite from Rust/Axum to NestJS/TypeScript.
- 22 feature modules (auth, servers, wipes, maps, plugins, players, console,
  chat, team, notifications, settings, schedules, analytics, alerts, status,
  store, webstore, admin, setup, migration, users, licenses)
- 39 TypeORM entities matching PostgreSQL schema (12 migrations)
- Common infrastructure: JWT/RBAC guards, decorators, exception filter
- NATS service with pub/sub/request-reply
- Socket.IO WebSocket gateway with NATS bridge
- Docker: NestJS Dockerfile + updated docker-compose.yml
- Zero compile errors (npx tsc --noEmit clean)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend-nest/src/entities/payment-order.entity.ts

@@ -0,0 +1,58 @@
+import { Entity, PrimaryGeneratedColumn, Column, ManyToOne, JoinColumn, Check } from 'typeorm';
+import { Module } from './module.entity';
+import { License } from './license.entity';
+
+@Entity('payment_orders')
+@Check(`"status" IN ('pending', 'completed', 'failed', 'refunded')`)
+export class PaymentOrder {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'varchar', length: 255, unique: true })
+  order_id: string;
+
+  @Column({ type: 'uuid', nullable: true })
+  module_id: string | null;
+
+  @Column({ type: 'uuid', nullable: true })
+  webstore_subscription_id: string | null;
+
+  @Column({ type: 'uuid' })
+  license_id: string;
+
+  @Column({ type: 'decimal', precision: 10, scale: 2 })
+  amount: number;
+
+  @Column({ type: 'varchar', length: 3, default: 'USD' })
+  currency: string;
+
+  @Column({ type: 'varchar', length: 50 })
+  status: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: true })
+  transaction_id: string | null;
+
+  @Column({ type: 'varchar', length: 255, nullable: true })
+  payer_email: string | null;
+
+  @Column({ type: 'timestamptz', default: () => 'NOW()' })
+  created_at: Date;
+
+  @Column({ type: 'timestamptz', nullable: true })
+  completed_at: Date | null;
+
+  @Column({ type: 'jsonb', nullable: true })
+  metadata: Record<string, any> | null;
+
+  @ManyToOne(() => Module, { onDelete: 'SET NULL', nullable: true })
+  @JoinColumn({ name: 'module_id' })
+  module: Module | null;
+
+  @ManyToOne(() => License, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'license_id' })
+  license: License;
+
+  @ManyToOne(() => License, { onDelete: 'SET NULL', nullable: true })
+  @JoinColumn({ name: 'webstore_subscription_id' })
+  webstore_subscription: License | null;
+}