Preloading not working for on-demand queries

[Raj1v]

minimal_repo.zip

• I've validated the bug against the latest version of DB packages

Describe the bug

When using syncMode: "on-demand" with a query collection, calling:

1. liveQuery.preload()
2. liveQuery.stateWhenReady()

returns immediately with 0 items, even though the fetch has been triggered.

The stateWhenReady() promise resolves before the data actually arrives.

---

To Reproduce

1. Create a query collection with syncMode: "on-demand"
2. Create a live query collection from it
3. Call await liveQuery.preload()
4. Call await liveQuery.stateWhenReady()
5. Check state.size — it's 0 even though queryFn was called

Minimal reproduction:

const postsCollection = createCollection(
  queryCollectionOptions({
    queryKey: ["posts"],
    queryFn: async () => {
      const res = await fetch("https://jsonplaceholder.typicode.com/posts");
      return res.json();
    },
    syncMode: "on-demand",
    queryClient,
    getKey: (item) => item.id,
  })
);

const posts = createLiveQueryCollection({
  query: (q) =>
    q
      .from({ post: postsCollection })
      .where(({ post }) => eq(post.userId, 1))
      .orderBy(({ post }) => post.id, "asc")
      .limit(10),
});

await posts.preload();

const state = await posts.stateWhenReady();
console.log(state.size); // ❌ 0 (expected: 10)

await sleep(2000);

const state2 = await posts.stateWhenReady();
console.log(state2.size); // ✅ 10 (data arrived after waiting)