docs: rank the destructive generator as item 0

It was written up in 4.7 but never made the work order, which is exactly how it
stayed dangerous in the first place.

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

examples/inter-app-api-showcase/apps/web/app/realtime/chat.ts

@@ -0,0 +1,20 @@
+// ws://<host>/realtime/chat — a simple broadcast room.
+//
+// The client side is the framework's realtime runtime; a page opts in with
+// `data-room="chat"`. Here we only handle room events.
+//
+//   client.send(msg)            → just this connection
+//   client.broadcast(msg)       → everyone else in the room
+//   client.room.broadcast(msg)  → everyone, including the sender
+import { defineRoom } from "@wrnexus/core";
+
+export default defineRoom({
+  onConnect(client) {
+    client.send({ type: "system", text: "connected" });
+  },
+
+  onMessage(client, msg) {
+    // Echo each message to the whole room so every tab stays in sync.
+    client.room.broadcast({ type: "message", data: msg });
+  },
+});