Solid 2: presence read on async derived store stays blank after resolution

[GabbeV]

Describe the bug

An in expression on a derived createStore stays blank after its pending source resolves. A sibling expression reading the source signal updates to resolved, but the presence expression neither shows present nor missing.

The component returns a pending promise from the store derivation, then sets the source signal to [1] and resolves that promise with [1] in the same timer callback. The read is inside <Loading>, which has finished showing its fallback.

Your Example Website or App

https://s.olid.uk/id/ffhim7PpQ5G0sPHlyO7JPg

Steps to Reproduce the Bug or Issue

1. Open the playground and click Build.
2. Wait for Source: resolved.
3. Observe that Presence: has no value.

Expected behavior

Presence: present. The derived store has resolved to [1], and length exists on that array.

Platform

• OS: Linux
• Browser: Chromium 153.0.8010.12
• Solid: 2.0.0-rc.13

[GabbeV]

A more application-shaped repro: https://s.olid.uk/id/MrvPyNcpS1GI7r0LqJ8FEw

1. Click Build. The To do lane initially contains “Review the proposal,” and the count reads All cards: 1.
2. Click Activity, then Board.
3. The count still reads All cards: 1, but the lane is empty.

The board view uses an async card source, a derived createStore, createOptimisticStore, and a keyed <For>. The count lives outside the view that is remounted. This shows the user-visible failure in a board-like setting; I have not established that it shares the same root cause as the direct presence-read repro above.