Add onNodeDoubleClick event emitter to Tree component

[Xeway]

See PR #17284.

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The PrimeNG Tree component lacks an event emitter for double-click events on nodes. Don't you think it would be nice to add this emitter?
It would work like onNodeContextMenuSelect emitter, except it's triggered when the user double click on a node.

Usage example:

<p-tree 
  [value]="nodes" 
  (onNodeDoubleClick)="handleNodeDoubleClick($event)">
</p-tree>

Event object:

{
  node: TreeNode; // The double-clicked node
  originalEvent: Event; // The original DOM event
}