fix(home): Start syncthing tray and wait

The tray might not yet be available, by specifying `--wait`, we can tell
syncthing-tray to wait for the tray to be available.

home/alex/home.nix

@@ -6,6 +6,7 @@
     ./programs/rofi
     ./programs/xmonad
     ./programs/jitsi-meet
+    ./programs/simplex-chat
     ./services/polybar
     ./services/dunst
     ./services/udiskie

home/alex/programs/simplex-chat/default.nix

@@ -0,0 +1,5 @@
+{ config, lib, pkgs, ... }:
+
+{
+  config.home.packages = [ pkgs.simplex-chat-desktop ];
+}

home/alex/services/syncthing/default.nix

@@ -3,6 +3,10 @@
 {
   config.services.syncthing = {
     enable = true;
-    tray.enable = true;
+    tray = {
+      enable = true;
+      command = "syncthingtray --wait";
+    };
+    extraOptions = [ "--wait" ];
   };
 }