Move scm VSCode extension from Andreas extension to new Cursorless developer extension

[pokey]

• See also https://github.com/cursorless-dev/cursorless/issues/1775
• See also https://github.com/cursorless-dev/cursorless/issues/1775

[AndreasArvidsson]

I do wonder if I should just create a separate repository and a separate extension for this. It is the standardized format that more people could have use of. I could even contribute settings where you could do regex or grep style patterns for the allowed capture names.