use the prebuild rust-sdk package

package.json

@@ -48,6 +48,7 @@
   },
   "devDependencies": {
     "@codecov/vite-plugin": "^1.3.0",
+    "@element-hq/matrix-rtc": "npm:@billcarsonfr/matrix-rtc@next",
     "@fontsource/inconsolata": "^5.1.0",
     "@fontsource/inter": "^5.1.0",
     "@formatjs/intl-durationformat": "^0.10.0",
@@ -82,7 +83,6 @@
     "@types/react-dom": "^19.0.0",
     "@types/sdp-transform": "^2.4.5",
     "@typescript-eslint/utils": "^8.61.0",
-    "@ubjs/core": "0.31.0-5",
     "@use-gesture/react": "^10.2.11",
     "@vector-im/compound-design-tokens": "^10.0.0",
     "@vector-im/compound-web": "^10.0.0",