Launching the editor opens a new custom terminal

[DaelonSuzuka]

Per feedback from @KoBeWi, this PR moves the process started by Open Workspace with Godot Editor back to a terminal (instead of a headless child process).

This time the terminal is implemented correctly, with a name + icon, and doesn't have a lingering prompt that you really shouldn't use. It also prints that the editor was stopped and what the exit code was.

Notes:

• Killing the terminal in VSCode (trash can button) kills the Godot Editor.
• Closing the Godot Editor does not kill the terminal, just in case there's some output you wanted to see.
• Running Open Workspace with Godot Editor again will close any existing windows and start a new one. I don't see a reason to open the same workspace multiple times.
• new settings:
  • godotTools.editor.verbose: Whether to launch the Godot Editor with the --verbose flag
  • godotTools.editor.reveal: Whether to reveal the terminal when launching the Godot Editor