[One Workflow] Keep execution indices green on single-node clusters

[skynetigor]

Issue

Beats single-node snapshot tests go yellow after Kibana start. Workflow execution indices were created with Elasticsearch’s default of 1 replica, which cannot allocate on one node. Health probes fail.

Approach

Same choice as .workflows-events: auto-expand replicas from 0 to 1. Apply it on create, and update existing indices on the next Kibana start so already-yellow clusters recover.

Behavior

On a single-node cluster, those indices run with 0 replicas and cluster health can stay green after boot. On two or more nodes they still get a replica. A failed settings update is logged and does not block startup.

Test plan

• Start Kibana against single-node ES and confirm cluster health is green after boot
• Confirm .workflows-executions and .workflows-step-executions have 0 replicas on one node
• Confirm a multi-node cluster still allocates a replica
• Restart Kibana against an existing yellow pair of those indices and confirm they go green

References

Closes elastic/security-team#19297

[infra-vault-gh-plugin-prod]

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[kibanamachine]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: f994649
• Build duration: 52 mins

Failed CI Steps

• Jest Tests #2
• Jest Tests #11
• Scout Lane #9 - stateful-classic / default

Metrics [docs]

Unknown metric groups

warm start memory

id	before	after	diff
post forced gc heap baseline	-	836761828	+836761828
post forced gc heap delta	-	-2576630	-2576630
post forced gc heap delta standard deviation	-	3276425	+3276425
post forced gc heap target	-	834185198	+834185198
tail heap delta	-	-3461674	-3461674
total			+1668185147

Test Failures

• [job] [logs] Scout Lane #9 - stateful-classic / default / local-stateful-classic - Document flyout v2 — alerts page entry - assignees: assigning the current user shows the avatar in the flyout header
• [job] [logs] Jest Tests #2 / suricata_row_renderer should render a suricata row even if it does not have a suricata signature
• [job] [logs] Jest Tests #11 / Testing AddDataProviderPopover Test Popover is visible