fix: value/checked not correctly set using spread

[adiguba]

Fix issue #15237 : "Using spread syntax '{...rest }' with props doesnt work correctly!"

Note : the issue is about the input input text value, but there's the same problem with checked.

set_attributes() use removeAttributes() which removes the attribute without impacting the JS state of value/checked, so the result is not constant.
This work only on the initial state, but not when the value/checked was previously set by JavaScript.

=> The value/checked properties must be set explicitly.

Note : I not launched lint and all tests because it generates strange errors on my config (before any change in the code).

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[changeset-bot]

🦋 Changeset detected

Latest commit: 0531f27

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

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svelte	Patch

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@15239

[adiguba]

added a fix for test form-default-value-spread : on initial rendering a null/undefined will use the value from defaultValue/defaultChecked

[trueadm]

Nice. I tested it out locally and it works really well, thank you for this fix :)