feat(nci): add Spark analytics Kubernetes manifests

Wire five Spark jobs (OpeningBook, PlayerStats, PlayerClustering,
PlayerGraph, LiveDashboard) to Kubernetes via native Spark-on-K8s mode.

- spark-analytics/base: ServiceAccount, RBAC Role/RoleBinding (driver
  executor pod management), two PVCs (10Gi output, 2Gi checkpoint),
  four CronJobs for batch analytics, one Deployment for the Structured
  Streaming live dashboard
- spark-analytics/eu-central-1-prod: namespace overlay pinning image
  to 0.1.0 with strategic merge patches that update both the container
  image field and the spark.kubernetes.container.image conf arg
- eu-central-1/argo-apps/spark-analytics: ArgoCD Application pointing
  at the prod overlay with automated prune+selfHeal sync

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

spark-analytics/base/pvc.yaml

@@ -0,0 +1,27 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: spark-analytics-output
+  labels:
+    app.kubernetes.io/name: spark-analytics
+    app.kubernetes.io/part-of: nowchess
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 10Gi
+---
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: spark-streaming-checkpoint
+  labels:
+    app.kubernetes.io/name: spark-analytics
+    app.kubernetes.io/part-of: nowchess
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 2Gi