fix: wait on dependencies of async bindings

[dummdidumm]

Correctly takes into account blockers for bindings. Also ensures it works for functional bindings.

During that I also noticed a bug in our nodes_end assignment logic, which the added test also regresses against.

Fixes #17092
Fixes #17090

Also discovered a related bug with static props also not awaiting the blockers, which is also fixed in this PR

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Tests and linting

• Run the tests with pnpm test and lint the project with pnpm lint

[changeset-bot]

🦋 Changeset detected

Latest commit: bf356a1

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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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@17120

[sillvva]

Testing this. This works:

<script lang="ts">
  await Promise.resolve();
	let search = $state("test");
</script>

<input type="text" bind:value={search} />

This does not:
https://svelte.dev/playground/7e4390edddab4574b9fb36eefde2bd7b?version=pr-17120

<script lang="ts">
  await Promise.resolve();
	let search = $state({ query: "test" });
</script>

<!-- works if you remove the binding below or the await above -->
<!-- also works if you move the await after the `$state()` -->
<!-- Cannot read properties of undefined (reading 'query') -->
<input type="text" bind:value={search.query} />

[dummdidumm]

Thank you for the test! Uncovered a dev-only bug with validation (it needed to wait on blockers, too)

[dummdidumm]

Found this was wrong for style directives, too

[Rich-Harris]

so glad you figured all this out so i didn't have to 😆