feat: support metadata and resource config for version probe jobs

[ashishch432]

Why

To support priortyclass, additional metadata support and a small resource footprint for jobs.

What

• VersionProbeSpec – new top-level field in both ClickHouseClusterSpec and KeeperClusterSpec.
  • Custom labels & annotations (via []MetadataItem for clean CRD compatibility).
  • Resource overrides (cpuRequest, cpuLimit, memoryRequest, memoryLimit) with defaults of 100m CPU / 128Mi memory.
• PodTemplateSpec now supports priorityClassName and runtimeClassName (applied to both main pods and the probe Job).
• Probe inheritance – the version probe Job now pulls NodeSelector, Tolerations, Affinity, TopologySpreadConstraints, ServiceAccountName, PriorityClassName, RuntimeClassName, and ImagePullSecrets from the cluster’s PodTemplateSpec.
• Identity isolation – probe Jobs now use the dedicated label app.kubernetes.io/instance: <cluster-name>-version-probe. This prevents E2E tests, Services, or health checks from accidentally counting the probe as a real cluster member.
• Unified metadata – custom labels/annotations are applied at both Job and Pod level for consistent troubleshooting.

Fixes #128. I did see #134 for job resources, but inheriting the full cluster resources may be much for a job.