fix: ng-helpers rejoint la surface dev.6, et son faux suit le contrat

test/adapter.test.ts

@@ -146,6 +146,21 @@ test("creating an index writes its field declaration, and nothing else", async (
   expect(world.contentsOf(ordinary)).toEqual([]);
 });
 
+test("an index is recorded in its creator's PUBLIC store, named by that store's reference", async () => {
+  const index = await as("alice", async (alice) => indexingOn(alice).create(FIELD));
+
+  // WHERE it landed, read off the fake rather than inferred from the call: an index a
+  // stranger cannot open is not an index, and the private store is one keystroke away
+  // (omitting the argument places it there).
+  expect(world.storeOf(index)).toBe(world.storesOf("alice").public);
+
+  // And HOW the store was named: the reference the accessor handed back, not a word.
+  // A store is told apart from every other reference only by being one of the three,
+  // so the accessor is the only thing that can produce it.
+  const placed = world.calls.filter((call) => call.entry === "storeRegistry.createEntityDoc").at(-1);
+  expect(placed?.args).toEqual([world.storesOf("alice").public]);
+});
+
 test("the write is the polyfill's canonical anchored form: the document named once, as the anchor", async () => {
   const index = await as("alice", async (alice) => indexingOn(alice).create(FIELD));
   const writes = world.calls.filter((call) => call.entry === "docs.sparqlUpdate");