feat: daemonset maxsurge to prevent unavailability on config changes

[dervoeti]

Description

Solves the problem reported in #817

Set maxSurge=1 and maxUnavailable=0 on the OPA DaemonSet so that during rolling updates, the new OPA pod is created and becomes ready before the old pod is terminated. This eliminates the availability gap that causes errors in products like Trino when OPA config changes trigger a DaemonSet restart.

DaemonSet maxSurge graduated to GA in Kubernetes 1.25, our current minimum supported Kubernetes version is 1.31.

Definition of Done Checklist

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Author

• Changes are OpenShift compatible
• CRD changes approved
• CRD documentation for all fields, following the style guide.
• Helm chart can be installed and deployed operator works
• Integration tests passed (for non trivial changes)
• Changes need to be "offline" compatible
• Links to generated (nightly) docs added
• Release note snippet added

Reviewer

• Code contains useful comments
• Code contains useful logging statements
• (Integration-)Test cases added
• Documentation added or updated. Follows the style guide.
• Changelog updated
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Acceptance

• Feature Tracker has been updated
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• Links to generated (nightly) docs added
• Release note snippet added
• Add type/deprecation label & add to the deprecation schedule
• Add type/experimental label & add to the experimental features tracker

[dervoeti]

Release note

The OPA DaemonSet now uses maxSurge=1 and maxUnavailable=0 for its rolling update strategy. During rolling updates (e.g. triggered by OPA config changes), a new OPA pod is created and must become ready before the old pod is terminated. This eliminates the brief availability gap that previously caused errors in products like Trino when the local OPA pod was unavailable during restarts.