vim: Fix relative line motion

Before this change up and down were in display co-ordinates, after this
change they are in fold coordinates (which matches the vim behaviour).

To make this work without causing usabliity problems, a bunch of extra
keyboard shortcuts now work:

- vim: `z {o,c}` to open,close a fold
- vim: `z f` to fold current visual selection
- vim: `g {j,k,up,down}` to move up/down a display line
- vim: `g {0,^,$,home,end}` to get to start/end of a display line

Fixes: zed-industries/community#1562

crates/vim/src/normal/substitute.rs

@@ -15,7 +15,10 @@ pub fn substitute(vim: &mut Vim, count: Option<usize>, cx: &mut WindowContext) {
                     }
                     if line_mode {
                         Motion::CurrentLine.expand_selection(map, selection, None, false);
-                        if let Some((point, _)) = Motion::FirstNonWhitespace.move_point(
+                        if let Some((point, _)) = (Motion::FirstNonWhitespace {
+                            display_lines: false,
+                        })
+                        .move_point(
                             map,
                             selection.start,
                             selection.goal,