enable plymouth and hide nixos stage 1 prints

hosts/deck/boot.nix

@@ -5,9 +5,19 @@ in
 {
   # Configure bootloader with lanzaboot and secureboot
   boot = {
+    consoleLogLevel = 0;
+    initrd.verbose = false;
     kernelModules = [ "nct6775" ];
     loader = {
-      systemd-boot.enable = true;
+      systemd-boot = {
+        enable = true;
+        configurationLimit = 5;
+        extraInstallCommands = ''
+          ${pkgs.coreutils}/bin/echo "timeout 0
+          console-mode 1
+          default nixos-*" > /boot/loader/loader.conf
+        '';
+      };
 
       efi = {
         canTouchEfiVariables = true;
@@ -15,14 +25,37 @@ in
       };
     };
 
+    plymouth = {
+      enable = true;
+    };
+
     kernelPackages = kernel;
 
     kernelParams = [
       "quiet"
       "amdgpu.ppfeaturemask=0xffffffff"
+      "splash"
+      "rd.systemd.show_status=false"
+      "rd.udev.log_level=3"
+      "udev.log_priority=3"
+      "loglevel=0"
+      "vt.global_cursor_default=0"
+      "rd.shell=0"
+      # Disable audit messages
+      "audit=0"
+      # Disable CPU mitigations messages
+      "mitigations=off"
     ];
-
-    consoleLogLevel = 3;
+    
     bootspec.enable = true;
   };
+  
+  # Further reduce systemd output
+  systemd = {
+    services.systemd-udev-settle.enable = false;
+    extraConfig = ''
+      ShowStatus=no
+      DefaultTimeoutStartSec=15s
+    '';
+  };
 }