Improve Python SI prompt adjustment on Windows

[Tyriar]

Also tracking the prompt >>> will help a lot with the default python setup, now that it's landing in the extension.

[anthonykim1]

Attempted to fix by defining Python prompt

		const pythonPrompt = lineText.match(/^(?<prompt>>>> )/g)?.groups?.prompt;
		if (pythonPrompt) {
			return {
				prompt: pythonPrompt,
				likelySingleLine: true
			};
		}

in vscode's commandDetectionCapability, but still getting colorless bubbles.

Opting into windows heuristic from the Python extension side via

is_windows="\x1b]633;P;IsWindows=True\x07",

as well as defining Python prompt seemed to set the decoration in less randomized location, but still getting colorless decoration for Windows pwsh users.

[Tyriar]

@anthonykim1 planning on this for March?

[anthonykim1]

@Tyriar Actually this has been merged already: https://github.com/microsoft/vscode/pull/204513/files
Sorry I forgot to link this one.