Tutorial - Expand Part 1 / Stores / Derived stores

[cobriensr]

Describe the problem

Derived stores explanation is short and cuts off with this suggestion box:

It's possible to derive a store from multiple inputs, and to explicitly set a value instead of returning it (which is useful for deriving values asynchronously). Consult the API reference for more information.

Describe the proposed solution

Include in the tutorial the suggestion box from above and expand the tutorial

Alternatives considered

N/A

Importance

would make my life easier

[Conduitry]

In Svelte 5, we're no longer mentioning derived stores in the tutorial. Closing.