vim: Rename wrapping keybindings + document cursor wrapping (#25694)

https://github.com/zed-industries/zed/pull/25663#issuecomment-2686095807

Renamed the `vim::Backspace` and `vim::Space` actions to
`vim::WrappingLeft` and `vim::WrappingRight` respectively. The old names
are still available, but they are marked as deprecated and users are
advised to use the new names.

Also added a paragraph to the docs describing how to enable wrapping
cursor navigation.

crates/vim/src/replace.rs

@@ -95,7 +95,7 @@ impl Vim {
                     .into_iter()
                     .filter_map(|selection| {
                         let end = selection.head();
-                        let start = motion::backspace(
+                        let start = motion::wrapping_left(
                             &map,
                             end.to_display_point(&map),
                             maybe_times.unwrap_or(1),