fix(sunshine): use Intel rendering and recover remote Niri sessions (#268)

- render Niri on the Intel iGPU while retaining NVIDIA-connected physical outputs
- encode Sunshine streams with Intel VAAPI and wait for a Niri output before startup
- load VKMS persistently for headless sessions and configure `Virtual-1` at 2560x1600@60
- let Moonlight request the stream bitrate instead of enforcing a 20 Mbps host cap
- remove unsupported Dynamic Boost and global NVIDIA session overrides
- grant Sunshine access to virtual input devices
- add a Nushell recovery helper that starts a temporary greetd/Niri session from SSH
- identify and safely replace normal, standalone, or previous transient Niri sessions
- launch the transient service in the background and verify greetd, Niri, and Sunshine before returning
- ignore local `.worktrees` directories and keep eval regression coverage focused on structural behavior

hosts/idols-ai/hardware-intel.nix

@@ -14,8 +14,17 @@
 
   # kvm virtualization support
   boot.initrd.kernelModules = [ ];
-  boot.kernelModules = [ "kvm-intel" ];
-  boot.extraModprobeConfig = "options kvm_intel nested=1";
+  boot.kernelModules = [
+    "kvm-intel"
+    # Provide a connected DRM output when the NVIDIA-attached monitors are off.
+    # Niri exposes it as Virtual-1 for headless Sunshine sessions.
+    "vkms"
+  ];
+  boot.extraModprobeConfig = ''
+    options kvm_intel nested=1
+    # Create Virtual-1 as soon as vkms loads, including during normal physical sessions.
+    options vkms create_default_dev=1
+  '';
   boot.extraModulePackages = [ ];
 
   # Intel Graphics

hosts/idols-ai/hardware-nvidia.nix

@@ -1,6 +1,5 @@
 {
   config,
-  lib,
   pkgs,
   ...
 }:
@@ -42,8 +41,6 @@
     # required by most wayland compositors!
     modesetting.enable = true;
     powerManagement.enable = true;
-
-    dynamicBoost.enable = lib.mkForce true;
   };
 
   hardware.nvidia-container-toolkit.enable = true;
@@ -54,9 +51,23 @@
   };
 
   services.sunshine.settings = {
-    max_bitrate = 20000; # in Kbps
-    # NVIDIA NVENC Encoder
-    nvenc_preset = 3; # 1(fastest + worst quality) - 7(slowest + best quality)
-    nvenc_twopass = "full_res"; # quarter_res / full_res.
+    adapter_name = "/dev/dri/by-path/pci-0000:00:02.0-render"; # Intel iGPU
+    encoder = "vaapi";
+  };
+
+  systemd.user.services.sunshine = {
+    after = [ "niri.service" ];
+    environment.LIBVA_DRIVER_NAME = "iHD";
+    preStart = ''
+      for _ in {1..20}; do
+        if ${config.programs.niri.package}/bin/niri msg outputs | ${pkgs.gnugrep}/bin/grep -q '^Output '; then
+          exit 0
+        fi
+        sleep 0.5
+      done
+
+      echo "Sunshine requires at least one Niri output" >&2
+      exit 1
+    '';
   };
 }

hosts/idols-ai/niri-hardware.kdl

@@ -1,4 +1,10 @@
 // running `niri msg outputs` to find outputs
+debug {
+    // Keep desktop rendering and ordinary applications on the Intel iGPU.
+    // Physical outputs remain on the NVIDIA GPU and use cross-GPU scanout.
+    render-drm-device "/dev/dri/by-path/pci-0000:00:02.0-render"
+}
+
 output "DP-1" {
     // Uncomment this line to disable this output.
     // off
@@ -37,6 +43,16 @@ output "HDMI-A-2" {
     position x=2560 y=0 // on the right of DP-2
 }
 
+output "Virtual-1" {
+    // Created by vkms in hardware-intel.nix. Sunshine captures this output when
+    // the NVIDIA-attached physical monitors are off. It remains available in
+    // normal physical sessions, with minor idle GPU and framebuffer overhead.
+    scale 1
+    transform "normal"
+    mode "2560x1600@60"
+    position x=0 y=0
+}
+
 // ============= Named Workspaces =============
 workspace "4entertainment" { open-on-output "DP-1"; }
 workspace "2browser" { open-on-output "DP-1"; }