Streaming with remote function instead of promise doesn't work on hard reload

[mkatrenik]

Describe the bug

When trying Streaming with promises with remote function instead of simple pending promise from loader, it behaves differently.

with simple promise - both client side nav and hard reload stream correctly
with remote function - client side nav works, but not hard reload - here it hangs until query is resolved and only then renders with tiny flash of pending indicator

as you can see in remote/+page.svelte - if you wrap remote query in async fn, it now behaves same as loader example

Reproduction

https://stackblitz.com/edit/svelte-remote-fn-streaming-issue?file=src%2Froutes%2F%2Blayout.svelte,src%2Froutes%2Fremote%2F%2Bpage.svelte,src%2Froutes%2Floader%2F%2Bpage.svelte

Logs

System Info

stackblitz conteiner

 System:
    OS: Linux 5.0 undefined
    CPU: (8) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 0 Bytes / 0 Bytes
    Shell: 1.0 - /bin/jsh
  Binaries:
    Node: 20.19.1 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 10.8.2 - /usr/local/bin/npm
    pnpm: 8.15.6 - /usr/local/bin/pnpm
  npmPackages:
    svelte: ^5.43.8 => 5.43.8

Severity

annoyance