fix: increase precompute memory limit to 56Gi for 61M MBP-10 snapshots

Previous 32Gi OOM'd with 148GB of MBP-10 data (61M snapshots ≈ 15GB
in memory + trades + OHLCV). ci-compile-cpu node has 64GB.

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

infra/k8s/argo/precompute-features-template.yaml

@@ -73,10 +73,10 @@ spec:
         resources:
           requests:
             cpu: "4"
-            memory: 8Gi
+            memory: 16Gi
           limits:
-            cpu: "16"
-            memory: 32Gi
+            cpu: "28"
+            memory: 56Gi
         volumeMounts:
           - name: training-data
             mountPath: /data