fix(home/fish): use helix OR vi keybinds, both together causes conflict

Author: Misterio77

home/gabriel/features/cli/fish/bindings.nix

@@ -10,8 +10,7 @@ in
 {
   programs.fish = {
     interactiveShellInit = ''
-      fish_vi_key_bindings
-      ${lib.optionalString useHelix "fish_helix_key_bindings"}
+      ${if useHelix then "fish_helix_key_bindings" else "fish_vi_key_bindings"}
       set fish_cursor_default     block      blink
       set fish_cursor_insert      line       blink
       set fish_cursor_replace_one underscore blink