feat(spark): deploy persistent Spark cluster with Web UI

- Add spark-cluster/base with Bitnami Spark chart 9.2.10 (master +
  2 workers), spark-events PVC (RWO/local-path), and Ingress resources
  for spark.nowchess.janis-eccarius.de (master UI) and
  spark-history.nowchess.janis-eccarius.de (history placeholder)
- Add spark-cluster/eu-central-1-prod overlay and ArgoCD Application
  (automated prune + selfHeal)
- Migrate all spark-analytics CronJobs and streaming Deployment from
  K8s-native mode (k8s://...) to Spark standalone (spark://spark-master:7077);
  drop kubernetes-specific --conf flags; add eventLog confs; mount
  spark-events PVC on all job pods

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

spark-cluster/base/charts/spark-9.2.10/spark/Chart.lock

@@ -0,0 +1,6 @@
+dependencies:
+- name: common
+  repository: oci://registry-1.docker.io/bitnamicharts
+  version: 2.22.0
+digest: sha256:a8fb2fc887ead658a89598a48acde5324196fbc0509503a3eaed50a710fbfe74
+generated: "2024-08-12T12:55:49.00370715Z"