vim: Implement named registers (#12895)

Release Notes:

- vim: Add support for register selection `"a`-`"z`, `"0`-`"9`, `"-`.
`"_` and `"%`
([#11511](https://github.com/zed-industries/zed/issues/11511))

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

crates/vim/src/mode_indicator.rs

@@ -39,9 +39,17 @@ impl ModeIndicator {
 
     fn current_operators_description(&self, vim: &Vim) -> String {
         vim.state()
-            .operator_stack
-            .iter()
-            .map(|item| item.id())
+            .pre_count
+            .map(|count| format!("{}", count))
+            .into_iter()
+            .chain(vim.state().selected_register.map(|reg| format!("\"{reg}")))
+            .chain(
+                vim.state()
+                    .operator_stack
+                    .iter()
+                    .map(|item| item.id().to_string()),
+            )
+            .chain(vim.state().post_count.map(|count| format!("{}", count)))
             .collect::<Vec<_>>()
             .join("")
     }