feat: warnings as a kubernetes events

[scanhex12]

Why

We want to track warnings from pods. This PR allows to add records from the system.warning table into k8s events

[CLAassistant]

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2 out of 3 committers have signed the CLA.

✅ GrigoryPervakov
✅ scanhex12
❌ Copilot
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[Copilot]

Pull request overview

This PR surfaces rows from ClickHouse's system.warnings table as Kubernetes Warning events on the ClickHouseCluster object. A new reconcile step (reconcileWarnings) polls every replica's system.warnings in parallel and emits one event per warning message via the existing event recorder, using a hash of the message as the event "action" to drive aggregation. An e2e test triggers a warning by setting max_table_num_to_warn: 1 and asserts both the row in system.warnings and the corresponding ClickHouseWarning event.

Changes:

• New Warnings step in the ClickHouse reconcile chain that calls a new commander.Warnings() helper and emits ClickHouseWarning events with hashed actions for dedup.
• New EventWarningRecord reason constant, WarningsPollInterval (30s) constant, and unconditional 30s requeue.
• e2e coverage plus a cert-manager install-wait timeout bump from 5m to 10m.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
api/v1alpha1/events.go	Adds EventWarningRecord event reason constant.
internal/controller/constants.go	Adds WarningsPollInterval = 30s.
internal/controller/clickhouse/commands.go	Adds commander.Warnings() querying system.warnings.
internal/controller/clickhouse/sync.go	Adds reconcileWarnings step + warningAction hash helper; emits per-warning events and unconditionally requeues.
test/e2e/clickhouse_e2e_test.go	New e2e test verifying warnings flow end-to-end.
test/testutil/utils.go	Bumps cert-manager webhook wait timeout from 5m to 10m.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

[GrigoryPervakov]

Operator CI / openshift-compat (pull_request) is failing, but it is not required to merge as infra is not stable yet.

[mintlify]

Docs PR opened: ClickHouse/mintlify-docs-dev#201

Synced upstream ClickHouse operator docs: added monitoring and scaling guides, External Secret config section, and AdditionalPort API reference.