fix: don't reset form after enhanced form submit

[Rich-Harris]

We reset input after a successful submission, but that's incorrect — we should only be resetting input when the form is reset, which is the default behaviour after a submission but shouldn't be when you use myform.enhance(...). In that case, the developer is responsible for resetting the form.

In any case, input = {} is incorrect — when the form is reset, we should use the actual values that are present (accounting for defaultValue and <select> initial options and so on). This PR adds a reset handler that fixes it.

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🦋 Changeset detected

Latest commit: d5045d4

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-14626-svelte.vercel.app/

[dummdidumm]

oh this was actually kind of a regression then, because prior to the enhanced remote forms enhance didn't reset

[vladshcherbin]

awesome fix 🥳