fix(ci): add volumes to ci-pipeline for compile-training templateRef

When using templateRef, Argo only borrows the template definition — not
spec-level volumes or volumeClaimTemplates from the source WorkflowTemplate.
Add workspace VCT, sccache PVC, and git-ssh-key secret at the ci-pipeline
spec level so compile-training's sub-templates can access them.

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

infra/k8s/argo/ci-pipeline-template.yaml

@@ -16,6 +16,24 @@ spec:
       app.kubernetes.io/part-of: foxhunt
   ttlStrategy:
     secondsAfterCompletion: 3600
+  # Volumes for compile-training (called via templateRef — spec-level volumes don't carry over)
+  volumeClaimTemplates:
+    - metadata:
+        name: workspace
+      spec:
+        accessModes: [ReadWriteOnce]
+        resources:
+          requests:
+            storage: 20Gi
+        storageClassName: scw-bssd
+  volumes:
+    - name: sccache
+      persistentVolumeClaim:
+        claimName: sccache-pvc
+    - name: git-ssh-key
+      secret:
+        secretName: argo-git-ssh-key
+        defaultMode: 256
   arguments:
     parameters:
       - name: commit-sha
@@ -321,14 +339,6 @@ spec:
         parameters:
           - name: service-package
           - name: commit-sha
-      volumes:
-        - name: sccache
-          persistentVolumeClaim:
-            claimName: sccache-pvc
-        - name: git-ssh-key
-          secret:
-            secretName: argo-git-ssh-key
-            defaultMode: 256
       container:
         image: rg.fr-par.scw.cloud/foxhunt-ci/ci-builder:latest
         command: ["/bin/sh", "-c"]