Command tracking should show glyphs next to rows and flash lines when navigating

[Tyriar]

Follow up for #45435

cmd+up/down on macOS should show some indication of the line that was scrolled to.

This will need some upstream changes.

[chrisdias]

testing #46594

if i have a few empty lines such as this:

pressing cmd+up appears to do nothing, so having some indication of where I am would be great.

[Tyriar]

@chrisdias yeah I would have liked to get this in but was a bit randomized this iteration.

[Tyriar]

Blocked on xtermjs/xterm.js#1852

[Tyriar]

Brought this to UX sync with a focus border outline that fades to 0 opacity over 2 seconds. But after it occurred to me that navigating the a symbol in the editor is the exact idea we're trying to get across which flashes a focus border briefly without animating. So going with that to align, we can change both if we want to tweak it:

[Tyriar]

Using 350ms:

vscode/src/vs/editor/contrib/gotoSymbol/browser/goToCommands.ts

Lines 214 to 222 in 12e6b0b

	if (highlight) {
	const modelNow = targetEditor.getModel();
	const ids = targetEditor.deltaDecorations([], [{ range, options: { description: 'symbol-navigate-action-highlight', className: 'symbolHighlight' } }]);
	setTimeout(() => {
	if (targetEditor.getModel() === modelNow) {
	targetEditor.deltaDecorations(ids, []);
	}
	}, 350);
	}

[Tyriar]