chore: rename $derived.call to $derived.by

[Rich-Harris]

Closes #10334. $derived.call is too close to Function.prototype.call and needs to be changed.

As the linked issue covers in exhaustive detail, there is no perfect name for this variant, but $derived.by is a good enough option that received broad support. Using $derived.call will result in an informative compiler error.

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[changeset-bot]

🦋 Changeset detected

Latest commit: 6134b0d

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[jgb-solutions]

I'll have to update a few of them in my codebase now, but who cares! I'm loving me some svelte 5. Been using Svelte for 2 weeks now and I love to live on the edge. :) Let's gooo!!!