Move move drag and drop util to @keystar/ui/drag-and-drop, update @keystar/ui LICENSE

[dcousens]

This pull request updates the Keystar design system package to clarify the origins and derivative nature of some of the work.

The @keystar/ui package license identifier has been updated to MIT and Apache-2.0, acknowledging the derivative nature of the work from Adobe's React Spectrum which it uses throughout. I have added the licensing headers to files that I found to be applicable, ensuring that the licensing attribution is transparent and respectful of the upstream work.

Additionally, the move utility has been relocated from the Keystatic package to @keystar/ui/drag-and-drop. This groups it logically and, now exported, allows it to be used by downstream developers when using @keystar/ui.

[changeset-bot]

🦋 Changeset detected

Latest commit: d0caff0

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

This PR includes changesets to release 14 packages

Name	Type
@keystar/ui	Patch
@keystatic/core	Patch
@keystar/docs	Patch
@example/next-app	Patch
@example/next-pages	Patch
keystatic-docs	Patch
@example/astro-content	Patch
@example/astro	Patch
@example/localization	Patch
@example/next-block-builder	Patch
@keystatic/remix-test-app	Patch
@keystatic/templates-astro	Patch
@keystatic/templates-nextjs	Patch
@keystatic/templates-remix	Patch

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