Helm chart: pod-shaping knobs missing on the operator deployment

[perbu]

Problem

The operator Deployment template (charts/varnish-gateway/templates/operator-deployment.yaml) exposes only nodeSelector, imagePullSecrets, resources, securityContext, and the two probes from values.yaml. For anyone running on a regulated or multi-tenant cluster, that's not enough.

Missing knobs:

• tolerations — required to schedule onto tainted nodes (e.g. dedicated control-plane / system pools).
• affinity / topologySpreadConstraints — required to control placement when operator.replicas > 1 (leader-election makes >1 replica reasonable for HA, and right now there's no way to spread across zones).
• priorityClassName — required for clusters where infra controllers must out-prioritise workload pods.
• podAnnotations / podLabels — needed for things like Linkerd injection annotations, Prometheus pod scrape hints, audit labels, etc.
• extraEnv — useful for GOMAXPROCS, GOMEMLIMIT, custom log levels, OTLP endpoints, and similar tunables without rebuilding.
• extraVolumes / extraVolumeMounts — needed for CA bundles, custom kubeconfig, etc.
• terminationGracePeriodSeconds is hard-coded to 10; should be overridable.

Proposal

Add these as optional top-level keys under operator: in values.yaml, defaulting to {} / [] / unset so they're no-ops for existing installs. Render with the standard {{- with .Values.operator.foo }} pattern so omission produces no output.

Out of scope

• Anything affecting the chaperone pods — those are templated by the operator at runtime, not by the chart. Plumbing pod-shaping into chaperones is a separate problem and probably belongs in GatewayClassParameters.