Element Picker: fixes "Not Found" name on removal prompt

[leekelleher]

Description

When deleting an item from the Element Picker, the removal confirmation message would have the name "Not Found". This was due to a missing feature in the Entity Data Picker, which has since been fixed in PR #22915... and this PR patches the Element Picker (data source) code.

[claude]

Claude finished @leekelleher's task in 1m 35s —— View job

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PR Review

Target: origin/release/18.0 · Based on commit: 6a416659e201eb1b24f6a5a29c0e00176a007556
· Skipped: 0 noise files out of 1 total

Adds createItemDataResolver to UmbElementTreePickerDataSource so the entity data picker can resolve a display name for element items when building the removal confirmation message — fixing the "Not Found" label on deletion.

• Other changes: Deletion confirmation dialogs for element picker items will now show the correct item name instead of "Not Found".

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No Critical, Important, or Suggestion findings. The implementation is minimal and correct:

• The createItemDataResolver property arrow function follows the exact same pattern as treePickableFilter in the same file and matches how the optional UmbPickerDataSource.createItemDataResolver factory is defined in types.ts.
• UmbElementItemDataResolver is the right resolver for this data source — it handles variant-aware name resolution for element items.
• Reordering type imports to group with other import type statements is a clean housekeeping change.

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Approved

This looks good to be merged as-is, but please do a manual sanity check and testing before merging.

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[Copilot]

Pull request overview

This PR updates the Elements “tree picker” data source to provide an item data resolver so that picked element items can resolve their display name (and related metadata) correctly in UI flows like the remove-confirmation dialog, aligning the Element Picker behavior with the resolver-based fix introduced for the Entity Data Picker.

Changes:

• Adds createItemDataResolver to UmbElementTreePickerDataSource.
• Uses UmbElementItemDataResolver to resolve element item display data via the consuming host context.