feat(hyprland/nsxiv): force nsxiv to start in tiled mode

home/emily/gui/hyprland/default.nix

···
               "nofocus"
               "noinitialfocus"
               "opacity 0.0 override"
+            ]) ++
+            (mkClassRules "Nsxiv" [ # So nsxiv actually starts in tiled mode
+              "tile"
             ]);
 
           decoration = {