chore: emit await_reactivity_loss in for await loops

[Ocean-OS]

Currently, await expressions not inside an async derived are wrapped in track_reactivity_loss in dev to warn of a reactivity loss.
However, for await loops are not. This PR fixes that.

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[changeset-bot]

🦋 Changeset detected

Latest commit: 88ba8e4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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svelte	Patch

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Playground

pnpm add https://pkg.pr.new/svelte@16521

[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-16521-svelte.vercel.app/

[Rich-Harris]

Clever solution, I like this much more than convoluted code transformations. I guess we need to decide whether we separately want to handle for await at the top level of components. Seems like a footgun but maybe there's a case where it would be useful? At the moment it won't compile (which is better than compiling but with broken reactivity)