A way to fully purge a previously deleted tag from database

[AquaSZS]

When you accidentally add a nonsense/typo tag, it stays in the database and shows up in tag suggestions permanently. I've been advised to use tag siblings to hide these bad tags, but that doesn't always make sense (example below).

Thus, I suggest there should be a way to purge certain deleted tags from database completely.

[FirstDagger]

Would be nice if that would include an option to remove all non-used tags.