override `$` to forbid partial matching

[moodymudskipper]

We generally don't want to rely on this.

We might have a function to toggle the override (create a function), this might also create a test that triggers a note that the override should be toggled off before release. We might also just gitignore the script containing the function definition.

The error should make it clear that it's artificial

[moodymudskipper]

This is the type of things that {strict} does