feat: Add moveBefore and moveAfter to useTreeData

[snowystinger]

Closes #5574

Matches the API for useListData and takes a target key instead of an index to simplify moving items around. Also accepts an array of keys to move in bulk.
Includes an error check to make sure you don't try to move an item inside itself.

✅ Pull Request Checklist:

• Included link to corresponding React Spectrum GitHub Issue.
• Added/updated unit tests and storybook for this change (for new code or code which already has tests).
• Filled out test instructions.
• Updated documentation (if it already exists for this component).
• Looked at the Accessibility Practices for this feature - Aria Practices

📝 Test Instructions:

🧢 Your Project:

[snowystinger]

there's an opportunity to optimize here if we rewrite updateTree a little so we don't generate a new array and new map for every single removal and instead batch the update. I've opted to get a working baseline based on existing functionality first though with tests.

[rspbot]

Build successful! 🎉

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• View the S2 storybook
• View the documentation

[rspbot]

## API Changes

@react-stately/data

/@react-stately/data:TreeData

 TreeData <T extends {}> {
   append: (Key | null, Array<{}>) => void
   getItem: (Key) => TreeNode<{}> | undefined
   insert: (Key | null, number, Array<{}>) => void
   insertAfter: (Key, Array<{}>) => void
   insertBefore: (Key, Array<{}>) => void
   items: Array<TreeNode<{}>>
   move: (Key, Key | null, number) => void
+  moveAfter: (Key, Iterable<Key>) => void
+  moveBefore: (Key, Iterable<Key>) => void
   prepend: (Key | null, Array<{}>) => void
   remove: (Array<Key>) => void
   removeSelectedItems: () => void
   selectedKeys: Set<Key>
   update: (Key, {}) => void
 }

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[reidbarber]

LGTM