Edit: Improve formatting logic, or provide generic formatting

[umpox]

What:

• Currently we use the users' default formatter to format the output of an Edit, immediately after it is applied to the document.
• This is ok but it's problematic because:
  • We're relying on another extension here, it needs to work well, fast and be bug-free. Otherwise users' just see that Cody produced some poorly formatted code.
• We have also had recent cases where the formatting logic seems to have broken completely, and removed all indentation. This may be due to a bug in VS Code but it still is out of our hands.

How:

• Explore if there's any other VS Code APIs available to us to format an portion of text to a users' liking.
• Provide our own agnostic formatting logic, it should:
  • Check the spaces/tabs settings in the editor.
  • Determine the correct insertionPoint of the edit, and adjust the indentation of all subsequent lines depending on this, and the configured tab/space settings.
    • Match the existing start, if editing a range of text
    • Determine the correct indentation of a new line, if inserting new text