Suggest Widget: Show Details For Selection Under Cursor

[Number-3434]

In the suggest widget, show the details (documentation) for the suggestion underneath the cursor.

Currently, you have to use the arrow keys (↑ Up Arrow and ↓ Down Arrow) to navigate the suggestions, which can be quite limiting especially when there are lots of suggestions, and you want to quickly browse through them.

https://github.com/microsoft/vscode/assets/115815794/54092c7e-d009-44d5-ae5d-a1c327c46a39