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/services/nats-bridge.service.ts

@@ -0,0 +1,44 @@
+import { Injectable, OnModuleInit, Logger } from '@nestjs/common';
+import { NatsService } from './nats.service';
+
+@Injectable()
+export class NatsBridgeService implements OnModuleInit {
+  private readonly logger = new Logger(NatsBridgeService.name);
+  private listeners: Map<string, Set<(event: string, data: unknown) => void>> = new Map();
+
+  constructor(private nats: NatsService) {}
+
+  onModuleInit() {
+    this.nats.subscribe('corrosion.*.companion.heartbeat', (data, subject) => {
+      const licenseId = subject.split('.')[1];
+      this.emit(licenseId, 'heartbeat', data);
+    });
+
+    this.nats.subscribe('corrosion.*.console.output', (data, subject) => {
+      const licenseId = subject.split('.')[1];
+      this.emit(licenseId, 'console_output', data);
+    });
+
+    this.logger.log('NATS bridge subscriptions initialized');
+  }
+
+  addListener(licenseId: string, callback: (event: string, data: unknown) => void): void {
+    if (!this.listeners.has(licenseId)) {
+      this.listeners.set(licenseId, new Set());
+    }
+    this.listeners.get(licenseId)!.add(callback);
+  }
+
+  removeListener(licenseId: string, callback: (event: string, data: unknown) => void): void {
+    this.listeners.get(licenseId)?.delete(callback);
+  }
+
+  private emit(licenseId: string, event: string, data: unknown): void {
+    const callbacks = this.listeners.get(licenseId);
+    if (callbacks) {
+      for (const cb of callbacks) {
+        cb(event, data);
+      }
+    }
+  }
+}