vim keybinding updates (#3057)

Release Notes:

- vim: Add ctrl-i to go forward
([#1732](https://github.com/zed-industries/community/issues/1732)).
ctrl-o was already supported.
- vim: Add `g <space>` to open the current snippet in its own file.
- vim: Escape will now return to normal mode even if completion menus
are open (use `ctrl-x ctrl-z` to hide menus, as in vim).
- vim: Add key bindings for Zed's various completion mechanisms:
- - `ctrl-x ctrl-o` to open the completion menu,
- -  `ctrl-x ctrl-l` to open the LSP action menu,
- - `ctrl-x ctrl-c` to trigger Copilot (requires configuring copilot),
- - `ctrl-x ctrl-a` to trigger the inline Assistant (requires
configuring openAI),

NOTE: we should add these to the docs before shipping 0.107 to stable.

crates/vim/src/insert.rs

@@ -16,6 +16,7 @@ fn normal_before(_: &mut Workspace, action: &NormalBefore, cx: &mut ViewContext<
         vim.stop_recording_immediately(action.boxed_clone());
         if count <= 1 || vim.workspace_state.replaying {
             vim.update_active_editor(cx, |editor, cx| {
+                editor.cancel(&Default::default(), cx);
                 editor.change_selections(Some(Autoscroll::fit()), cx, |s| {
                     s.move_cursors_with(|map, mut cursor, _| {
                         *cursor.column_mut() = cursor.column().saturating_sub(1);