hosts: homes: mousqueton: use 'trueColorTerminals'

Ah, much better with an actual option for this :-).

hosts/homes/ambroisie@mousqueton/default.nix

@@ -20,8 +20,6 @@
   # I use scripts that use the passthrough sequence often on this host
   my.home.tmux.enablePassthrough = true;
 
-  programs.tmux.extraConfig = ''
-    # Setup 24-bit color explicitly, as the default terminfo entry does not
-    set-option -sa terminal-overrides ",xterm-256color:Tc"
-  '';
+  # HTerm uses `xterm-256color` as its `$TERM`, so use that here
+  my.home.tmux.trueColorTerminals = [ "xterm-256color" ];
 }