feat: correctly handle ipv4-only envs

[GrigoryPervakov]

Why

listen_host: "::" do not work in ipv4 only envs and require extra config to run.
listen_try is acceptable as a liveness probe that checks that the port is being listened to.

What

Change the default listen config to work in IPv4-only environments by default

Related Issues

Fixes #169

[Copilot]

Pull request overview

Updates the operator’s generated ClickHouse (and Keeper) network listening configuration so clusters start cleanly in IPv4-only environments by default, avoiding failures from an IPv6-only listen_host: "::" binding.

Changes:

• Switch ClickHouse server default listen_host to include both :: and 0.0.0.0, and enable listen_try.
• Update ClickHouse Keeper generated config to emit multiple listen_host entries and enable listen_try.
• Remove now-unnecessary extraConfig.listen_host: "0.0.0.0" overrides from EKS/GKE example manifests.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
internal/controller/keeper/templates.go	Generates Keeper YAML config with dual-stack listen_host and listen_try enabled.
internal/controller/clickhouse/templates/network.yaml.tmpl	Adjusts default ClickHouse server network config to dual-stack listen_host plus listen_try.
examples/gcp_gke_ssd.yaml	Removes redundant IPv4 listen_host override from the example.
examples/aws_eks_gp3.yaml	Removes redundant IPv4 listen_host override from the example.

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