Make ctrl-alt-b / cmd-alt-b toggle right dock (#33190)

Closes: https://github.com/zed-industries/zed/issues/33147

In VSCode ctrl-alt-b / cmd-alt-b toggles the right dock. Zed should
follow this behavior.

See also:
- https://github.com/zed-industries/zed/pull/31630

Release Notes:

- N/A

assets/keymaps/linux/cursor.json

@@ -8,7 +8,6 @@
       "ctrl-shift-i": "agent::ToggleFocus",
       "ctrl-l": "agent::ToggleFocus",
       "ctrl-shift-l": "agent::ToggleFocus",
-      "ctrl-alt-b": "agent::ToggleFocus",
       "ctrl-shift-j": "agent::OpenConfiguration"
     }
   },
@@ -42,7 +41,6 @@
       "ctrl-shift-i": "workspace::ToggleRightDock",
       "ctrl-l": "workspace::ToggleRightDock",
       "ctrl-shift-l": "workspace::ToggleRightDock",
-      "ctrl-alt-b": "workspace::ToggleRightDock",
       "ctrl-w": "workspace::ToggleRightDock", // technically should close chat
       "ctrl-.": "agent::ToggleProfileSelector",
       "ctrl-/": "agent::ToggleModelSelector",