docs: Kubernetes Operator v2.7.0 — pod lifecycle, sidecars, extra volumes

[mintlify]

Summary

Documents the user-facing features shipped in Kubernetes Operator v2.7.0.

What shipped in v2.7.0

Five new optional fields on RestateCluster spec.compute pass through to the StatefulSet pod template:

• lifecycle — postStart / preStop hooks for the Restate container (e.g. graceful-shutdown scripts).
• sidecars — native sidecar containers (log shippers, proxies, metrics exporters) that start before and terminate after Restate. Requires Kubernetes 1.29+.
• terminationGracePeriodSeconds — overrides the previously hardcoded 60-second grace period.
• extraVolumes — additional pod volumes (e.g. a ConfigMap of hook scripts).
• extraVolumeMounts — additional volume mounts on the Restate container.

Volume and mount collisions with operator-managed resources are validated up front with a clear error.

Documentation changes

• docs/changelog/operator.mdx — added v2.7.0 entry with full release notes, usage example, and upgrade instructions.
• docs/server/deploy/kubernetes.mdx — added a new "Pod lifecycle hooks, sidecars, and extra volumes" section with per-field explanations, caveats, and a full YAML example. Updated the features list to include the new capabilities.

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