UXP Plugin Panel Does Not Recognize Drag and Drop Events in InDesign

Description:
The custom UXP plugin panel in InDesign does not support drag and drop events. When an object is clicked and dragged from the InDesign document to the plugin panel, the panel does not recognize the drag and drop events. This prevents the simulation of drag and drop actions within the panel. Even though actual dragging and dropping actions like copying can be simulated using app.selection to capture the objects, the drag and drop events within the panel are not being triggered.

Steps to Reproduce:
Open InDesign.
Load the custom UXP plugin.
Open the custom panel from the plugin menu.
Click and drag an object from the InDesign document to the plugin panel.
Expected Behavior:
The panel should recognize the drag and drop events, allowing for the simulation of drag and drop actions within the panel.

Actual Behavior:
The panel does not recognize the drag and drop events, preventing the simulation of these actions.

Start with the reproduction steps in the issue using InDesign and the custom UXP panel, then inspect the UXP documentation covering panel drag-and-drop events. Determine whether the documented behavior matches the report and identify the relevant documentation entry point; done means the behavior is clarified or the missing documentation change is precisely scoped.

Written by the indexing model from the issue text.