Automatically apply terminal environment changes to terminals that have not been interacted with #100193
Description
If extensions modify terminal variables (using ExtensionContext.EnvironmentVariableCollection), terminals need to be reloaded. If this has happened seconds after the terminal was created (eg. during startup/project open) it seems reasonable that the (unused) terminal could just be immediately recreated, rather than the icon being shown and the user having to do it.
(this was mentioned at #99874 (comment)).