Git commit modal command (#26405)

Fix KeyBinding::for_action() to use the active focus handle instead of
what was
rendered last.

This makes the UI consistently chose the cmd-escape binding for close
(because escape in the editor is editor::Cancel?),
so force it to be "escape"

Release Notes:

- git: Fixed escape tooltip in commit modal

assets/keymaps/default-linux.json

@@ -746,6 +746,7 @@
   {
     "context": "GitCommit > Editor",
     "bindings": {
+      "escape": "menu::Cancel",
       "enter": "editor::Newline",
       "ctrl-enter": "git::Commit",
       "alt-l": "git::GenerateCommitMessage"