chore: initialize from frontend template 4dc033c

tests/fixtures/browser-file-storage-boundaries/allowed/cross-context-host.ts

@@ -0,0 +1,6 @@
+export function createOwnedCrossContextCapabilities() {
+  return {
+    channel: new BroadcastChannel("owned-cross-context-fixture"),
+    storage: localStorage,
+  };
+}