Add action to add a type annotation

What we want

We will make it so that the “clear” / “change” action, when applied to “type”, if there is no existing type annotation, will insert a : and leave the cursor afterwords so that the user can add a type.

For example:

function foo() {
  return "hello" // cursor at end of this line
}

User says “change type”, results in

function foo(): <cursor-here> {
  return "hello"
}

Implementation

We will leverage https://github.com/pokey/cursorless-vscode/issues/210 to make it so that target returned from “type” knows how to insert itself

[AndreasArvidsson]

When the action is called change it makes perfect sense. As a clear command I’m a bit ambivalent. Also adding a new action for this very niche case is probably unnecessary.

[AndreasArvidsson]

Yes if the action is going to be change on even add the action name is definitely incorrect