feat(challenge30): interop rxjs signal

apps/interop-rxjs-signal/src/main.ts

@@ -0,0 +1,7 @@
+import { bootstrapApplication } from '@angular/platform-browser';
+import { appConfig } from './app/app.config';
+import { AppComponent } from './app/app.component';
+
+bootstrapApplication(AppComponent, appConfig).catch((err) =>
+  console.error(err)
+);