infra: add suspended CronWorkflow for nightly GPU test runs

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

infra/k8s/argo/gpu-test-nightly-cron.yaml

@@ -0,0 +1,25 @@
+# infra/k8s/argo/gpu-test-nightly-cron.yaml
+apiVersion: argoproj.io/v1alpha1
+kind: CronWorkflow
+metadata:
+  name: gpu-test-nightly
+  namespace: foxhunt
+  labels:
+    app.kubernetes.io/name: gpu-test-nightly
+    app.kubernetes.io/part-of: foxhunt
+spec:
+  schedule: "0 2 * * *"
+  timezone: "UTC"
+  suspend: true  # Enable when ready: kubectl patch cronworkflow gpu-test-nightly -n foxhunt -p '{"spec":{"suspend":false}}'
+  concurrencyPolicy: Replace
+  successfulJobsHistoryLimit: 3
+  failedJobsHistoryLimit: 5
+  workflowSpec:
+    workflowTemplateRef:
+      name: gpu-test-pipeline
+    arguments:
+      parameters:
+        - name: models
+          value: "dqn,ppo,tft,mamba2,tggn,tlob,liquid,kan,xlstm,diffusion"
+        - name: commit-ref
+          value: "main"