fix tab drag and drop

[meganrogge]

fix #275592

Adding the chat entry wrapped the tabs list in an extra container. When you would drag a tab into the empty area (which is now that container instead of the list), the list’s drop handler would never runs. The fix watches for drops on the container/chat entry, recognizes terminal drags, and forwards them to the usual “move to end” logic, so behavior matches what we had before.

demo.mov

[Copilot]

Pull Request Overview

This PR adds drag-and-drop support for the empty area in the terminal tabs view, allowing users to drop terminal tabs onto the empty space at the end of the tab list.

• Adds event listeners for drag-and-drop operations (dragenter, dragover, dragleave, drop) on the tab container
• Implements logic to handle dropping terminals into the empty area, moving them to the end of the tab list
• Adds visual feedback with CSS styling when dragging over the drop target area

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/vs/workbench/contrib/terminal/browser/terminalTabbedView.ts	Adds drag-and-drop event handlers, helper methods, and state management for empty area terminal drops
src/vs/workbench/contrib/terminal/browser/media/terminal.css	Adds visual styling for the drop target indicator on the tabs list container