acp: Disable external agents over SSH (#37402)

Follow-up to #37377 

Show a clearer error here until SSH support is implemented.

Release Notes:

- N/A

crates/vim/src/visual.rs

@@ -216,7 +216,6 @@ impl Vim {
                         // If the file ends with a newline (which is common) we don't do this.
                         // so that if you go to the end of such a file you can use "up" to go
                         // to the previous line and have it work somewhat as expected.
-                        #[allow(clippy::nonminimal_bool)]
                         if !selection.reversed
                             && !selection.is_empty()
                             && !(selection.end.column() == 0 && selection.end == map.max_point())