Bake GeForce NOW native Linux app (beta) via first-boot installer

NVIDIA's client ships from their own flatpak repo (com.nvidia.geforcenow),
which default-flatpaks can't add alongside Flathub — so a stamped oneshot
service installs it on first boot with retries. Docs note the BC-250 has
no hardware video decode: streams are CPU-decoded, keep to 1080p.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

recipes/bc250-console-gnome.yml

@@ -24,7 +24,7 @@ modules:
 
   - type: script
     snippets:
-      - chmod 0755 /usr/bin/bc250-remote-setup /usr/bin/bc250-steam-bpm-autostart
+      - chmod 0755 /usr/bin/bc250-remote-setup /usr/bin/bc250-steam-bpm-autostart /usr/bin/bc250-gfn-install
       - dconf update # compile the local.d/gdm.d console defaults into the dconf dbs
 
   - type: default-flatpaks@v1
@@ -41,6 +41,7 @@ modules:
         - cyan-skillfish-governor-smu.service
         - sshd.service
         - tailscaled.service # idle until 'sudo tailscale up'
+        - bc250-gfn-install.service # GeForce NOW beta from NVIDIA's flatpak repo (first boot)
       masked:
         - hhd.service # Handheld Daemon crash-loops on BC-250
         # Always-on console: hard-block every suspend path (the box must