Switch nvidia device plugin to CDI device list strategy

Use CDI-based device injection instead of nvidia-container-runtime.
The NixOS nvidia-container-toolkit module generates CDI specs with all
the correct nix store paths, so containerd's native CDI support handles
GPU device and library injection without a custom runtime.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

argocd/manifests/nvidia-device-plugin/daemonset.yaml

@@ -23,6 +23,9 @@ spec:
       containers:
         - name: nvidia-device-plugin
           image: nvcr.io/nvidia/k8s-device-plugin:v0.18.2
+          args:
+            - --device-list-strategy=cdi-cri
+            - --cdi-annotation-prefix=cdi.k8s.io/
           env:
             - name: LD_LIBRARY_PATH
               value: /run/nvidia/lib