feat(config): add Atuin AI inline integration and keybinding

dot_config/fish/functions/ai.fish

@@ -11,3 +11,5 @@ function ai --description 'Choose and launch an AI CLI via gum'
             $choice
     end
 end
+
+

dot_config/fish/functions/fish_user_key_bindings.fish

@@ -18,6 +18,7 @@ function fish_user_key_bindings
         bind -M $mode ctrl-o 'gho; commandline -f repaint'
         bind -M $mode ctrl-p 'pj; commandline -f repaint'
         bind -M $mode ctrl-a 'omp; commandline -f repaint'
+        bind -M $mode ctrl-w 'atuin ai inline; commandline -f repaint'
 
         # Arrow keys: atuin owns up (bound from config.fish, survives the
         # fish_vi_key_bindings reset above because that only erases presets),