fix: add volumes to all train-* templates for compile-and-train compat

templateRef doesn't inherit workflow-level volumes from the referenced
template. All 3 train wrappers (DQN, PPO, supervised) now define
git-ssh-key, training-data, cargo-target-cuda volumes and workspace
volumeClaimTemplate locally.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

infra/k8s/argo/train-dqn-template.yaml

@@ -65,6 +65,30 @@ spec:
       - name: cuda-compute-cap
         value: "90"
 
+  # Volumes required by compile-and-train steps
+  volumes:
+    - name: git-ssh-key
+      secret:
+        secretName: argo-git-ssh-key
+        defaultMode: 256
+    - name: training-data
+      persistentVolumeClaim:
+        claimName: training-data-pvc
+        readOnly: true
+    - name: cargo-target-cuda
+      persistentVolumeClaim:
+        claimName: cargo-target-cuda
+
+  volumeClaimTemplates:
+    - metadata:
+        name: workspace
+      spec:
+        accessModes: ["ReadWriteOnce"]
+        storageClassName: scw-bssd
+        resources:
+          requests:
+            storage: 5Gi
+
   templates:
     - name: pipeline
       steps:

infra/k8s/argo/train-ppo-template.yaml

@@ -69,6 +69,30 @@ spec:
       - name: cuda-compute-cap
         value: "90"
 
+  # Volumes required by compile-and-train steps
+  volumes:
+    - name: git-ssh-key
+      secret:
+        secretName: argo-git-ssh-key
+        defaultMode: 256
+    - name: training-data
+      persistentVolumeClaim:
+        claimName: training-data-pvc
+        readOnly: true
+    - name: cargo-target-cuda
+      persistentVolumeClaim:
+        claimName: cargo-target-cuda
+
+  volumeClaimTemplates:
+    - metadata:
+        name: workspace
+      spec:
+        accessModes: ["ReadWriteOnce"]
+        storageClassName: scw-bssd
+        resources:
+          requests:
+            storage: 5Gi
+
   templates:
     - name: pipeline
       steps:

infra/k8s/argo/train-supervised-template.yaml

@@ -73,6 +73,30 @@ spec:
       - name: cuda-compute-cap
         value: "90"
 
+  # Volumes required by compile-and-train steps
+  volumes:
+    - name: git-ssh-key
+      secret:
+        secretName: argo-git-ssh-key
+        defaultMode: 256
+    - name: training-data
+      persistentVolumeClaim:
+        claimName: training-data-pvc
+        readOnly: true
+    - name: cargo-target-cuda
+      persistentVolumeClaim:
+        claimName: cargo-target-cuda
+
+  volumeClaimTemplates:
+    - metadata:
+        name: workspace
+      spec:
+        accessModes: ["ReadWriteOnce"]
+        storageClassName: scw-bssd
+        resources:
+          requests:
+            storage: 5Gi
+
   templates:
     - name: pipeline
       steps: