feat(nix): enhance WezTerm and Fish configuration

- Enabled scroll bar and added conditional fullscreen key handling in `wezterm.lua` for better usability.
- Updated Fish shell to set global `LESS` mouse support for improved navigation.

modules/home/cli-apps/fish/default.nix

@@ -19,6 +19,7 @@ in
       enable = true;
       interactiveShellInit = ''
         set fish_greeting # Disable greeting
+        set -gx LESS '--mouse'
         function msh --wraps mosh --description 'mosh with tmux'
           if not set -q argv[1]
             echo 'Usage: msh [user@]host [command]'