Fix browser WebSocket bundle

frontend/vite.config.mts

@@ -1,8 +1,16 @@
 import { defineConfig } from 'vite';
 import vue from '@vitejs/plugin-vue';
+import { resolve } from 'node:path';
 
 export default defineConfig({
   plugins: [vue()],
+  resolve: {
+    alias: {
+      // stompjs' package entry also imports its Node.js transport. Use the
+      // browser-only build so Vite does not emit a bare "websocket" import.
+      stompjs: resolve(__dirname, 'node_modules/stompjs/lib/stomp.js'),
+    },
+  },
   define: {
     global: 'globalThis',
   },
@@ -21,4 +29,3 @@ export default defineConfig({
     }
   }
 });
-