fix: lower download template resources to fit platform nodes

500m/512Mi request fits alongside existing platform workloads.
Download is I/O-bound, not CPU-bound.

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

infra/k8s/argo/databento-download-template.yaml

@@ -78,11 +78,11 @@ spec:
                 key: api-key
         resources:
           requests:
+            cpu: 500m
+            memory: 512Mi
+          limits:
             cpu: "2"
             memory: 4Gi
-          limits:
-            cpu: "8"
-            memory: 16Gi
         volumeMounts:
           - name: training-data
             mountPath: /data