feat: file upload

[Hugos68]

Linked Issue

Closes #3637

Description

Adds the FileUpload component

Checklist

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[changeset-bot]

🦋 Changeset detected

Latest commit: 7255c93

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

This PR includes changesets to release 3 packages

Name	Type
@skeletonlabs/skeleton-common	Minor
@skeletonlabs/skeleton-svelte	Minor
@skeletonlabs/skeleton-react	Minor

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[Hugos68]

@endigo9740 I've requested a review for the following:

• React logic/structure pass
• Svelte logic/structure pass (Should be identical to React)
• Common style pass

Docs are missing, you can use react and svelte playgrounds