Consider adding a short delay before debug toolbar appears

[gjsjohnmurray]

Using the latest vscode-mock-debug in a VS Code - OSS that I just built from master, the Run button makes the debug toolbar appear, then change, then disappear when the run has ended.

Can anything be done to prevent this unnecessary activity>

Originally posted by @gjsjohnmurray in #92269 (comment)

[isidorn]

Thanks for creating this issue! I think what you are saying and it makes sense. We should show the toolbar with a slight delay, now the open question is when to show it with a delay and when to immediatly show it.

[weinand]

The toolbar must become visible on first change. E.g. the debugger breaks and the "pause" button turns into a "continue" button. If nothing is happening, it is OK to show the toolbar after a delay, e.g. 300 ms.

[isidorn]

We can do that. But what is the right number, because 300ms for example would still show the debug toolbar in the examlpe above, it would just be shorter and look more like a UX glitch.

[weinand]

The question is: what delay are users willing to accept when they start a debug session and are not immediately hitting a breakpoint.

[isidorn]

Let's close as dup of #84228