vim lifecycle (#7647)

Release Notes:

- Fixed :0 and :% in vim mode
([#4303](https://github.com/zed-industries/zed/issues/4303)).
- Improved keymap loading to not load vim key bindings unless vim is
enabled

**or**

- N/A

crates/vim/src/state.rs

@@ -169,7 +169,6 @@ impl EditorState {
 
     pub fn keymap_context_layer(&self) -> KeyContext {
         let mut context = KeyContext::default();
-        context.add("VimEnabled");
         context.set(
             "vim_mode",
             match self.mode {