fix(api): WS gateways crashed on first forwarded event — WebSocket.OPEN undefined at runtime

Lesson 10 in the flesh: the onApplicationBootstrap fix made the NATS->
WS bridge actually deliver events for the first time, which instantly
crashed the API. esModuleInterop is off, so 'import WebSocket from ws'
compiles to ws_1.default = undefined; WebSocket.OPEN threw
'Cannot read properties of undefined' and killed the process on the
first heartbeat forward. All three WS guard sites (nats-bridge x2,
console gateway) switched to the import-agnostic instance constant
client.OPEN. Latent in every build — never hit because the bridge was
dead-on-boot until today.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend-nest/src/gateways/nats-bridge.gateway.ts

@@ -71,7 +71,10 @@ export class NatsBridgeGateway implements OnGatewayConnection, OnGatewayDisconne
 
         // Subscribe to NATS events for this license
         const listener = (event: string, data: unknown) => {
-          if (client.readyState === WebSocket.OPEN) {
+          // client.OPEN (instance constant) — NOT WebSocket.OPEN: with
+          // esModuleInterop off, the default `ws` import is undefined at
+          // runtime, so the static crashes. The instance constant is safe.
+          if (client.readyState === client.OPEN) {
             client.send(JSON.stringify({
               type: 'event',
               license_id: payload.license_id,

backend-nest/src/modules/console/console.gateway.ts

@@ -108,7 +108,9 @@ export class ConsoleGateway implements OnGatewayConnection, OnGatewayDisconnect
 
     const message = JSON.stringify({ event, data });
     for (const client of clients) {
-      if (client.readyState === WebSocket.OPEN) {
+      // client.OPEN, not WebSocket.OPEN — esModuleInterop is off so the
+      // default `ws` import is undefined at runtime (would crash on forward).
+      if (client.readyState === client.OPEN) {
         client.send(message);
       }
     }