[Draggable] Implement Manual DOM Delta Strategy for Live Component Dragging

Implement a robust "Manual DOM Delta" strategy to enable dragging of live components without losing state.

Problem: Dragging components typically involves moving them in the VDOM tree, which triggers a destroy/create cycle for the underlying DOM node. This breaks stateful elements like OffscreenCanvas or Iframe that rely on a persistent DOM instance.

Solution:

1. DragZone: Update createDragProxy to use Neo.applyDeltas for a manual move operation.

   • Instead of modifying the owner's items config (VDOM), we manually move the component's DOM node into the DragProxy.
   • We manually insert a placeholder vnode (fetched via Neo.vdom.Helper) into the owner's DOM to maintain the layout gap.
   • Configured DragProxyContainer with parentComponent: me.owner to maintain logical linkage for event bubbling.
   • Ensured neo-draggable class is on the proxy config to support event delegation.

2. SortZone: Update onDragEnd to perform a manual restoration.

   • Before calling moveTo (which syncs the VDOM), we manually move the component's DOM node back to its correct visual position in the owner and remove the placeholder node.
   • This ensures the VDOM update sees a DOM structure that matches its expectation, preventing a destructive reconciliation.
   • Corrected fromIndex calculation to use me.dragComponent (live reference) instead of proxy items.
   • Updated updateItem to handle the placeholder (mapped index -1) and redirect updates appropriately.

Changed Files:

• src/draggable/DragZone.mjs
• src/draggable/container/SortZone.mjs