The easiest way to type text with an AppleScript is to run:
tell application "System Events" to keystroke "foo bar"
You can trigger this with a keyboard shortcut by creating a new Quick Action (previously called Service) in Automator. Set it to receive No Input, and then drag Run AppleScript from the left pane to the right.
It should look like this:
Save it, and then assign a keyboard shortcut to this Service under System Preferences » Keyboard » Keyboard Shortcuts.
In case you are a CJK user using Mac, Ctrl+Space will not work, since it is used to switch IMEs.
There is another keyboard shortcut for triggering suggestions:
Also see this post.
VS code version: 1.41.1