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

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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]

This will send an event for every warning on every reconciliation. We need a way to deduplicate it

[scanhex12]

kubernetes does deduplication by itself - https://github.com/kubernetes/design-proposals-archive/blob/main/instrumentation/events-redesign.md

Deduplication logic groups together Event which have the same:

Source Component and Host
InvolvedObject Kind, Namespace, Name, API version and UID,
Type (works as Severity)
Reason

[scanhex12]

btw that's why we need to add a hash in warningAction. Otherwise it will merge all messages into one and my test will become flaky