waybar: Add river modules,Update for new nerdfonts

Added a window entry on the bar for the currently displayed window. If
it annoys me I will delete it again but it helps distinguish the active
and the inactive output.
Also added the current river *mode* which is a lovely feature to have,
though I would like to hide it if no mode (other than normal) is
currently active.

desktop/.config/waybar/style.css

@@ -2,6 +2,7 @@
     border: none;
     border-radius: 0;
     min-height: 0;
+    font-family: Iosevka Nerd Font, Iosevka, monospace;
 }
 
 window#waybar {
@@ -57,6 +58,7 @@ window#waybar.hidden {
 #mode,
 #idle_inhibitor,
 #mpd,
+#window,
 #custom-archupdates,
 #custom-wireguard,
 #custom-events,
@@ -82,6 +84,14 @@ window#waybar.hidden {
     background-color: @base02;
 }
 
+/* Mark active output through highlighted window background */
+#window {
+    background-color: transparent;
+}
+#window.focused {
+    background-color: @base01;
+}
+
 #battery.warning {
     background-color: @base09;
     color: @base00;