bug(jans-fido2): metrics aggregation logs spurious "ou=node is not configured" ConfigurationException in single-node mode

Describe the bug

The jans-fido2 metrics aggregation scheduler logged an io.jans.exception.ConfigurationException: ou=node is not configured in static configuration of AS (jansConfStatic). with a full stack trace on every aggregation run (hourly/daily/weekly/monthly) in single-node deployments. Fido2MetricsAggregationScheduler.initializeClusterEnvironment() treated the deployment as a cluster whenever the Fido2ClusterNodeService CDI bean was present (always, since it's @ApplicationScoped), but cluster coordination needs ou=node in jansConfStatic, which is absent in the default single-node setup. Every cluster call (getClusterNodesLive() via startPeriodicLockUpdates()) then threw, and the exception was logged at ERROR level — making a healthy deployment look broken. Aggregation still completed via existing fallbacks, so this was misleading log noise rather than a functional failure.

To Reproduce
Steps to reproduce the behavior:

Deploy jans-fido2 in a default single-node setup (no ou=node configured in jansConfStatic).
Enable FIDO2 metrics and aggregation (fido2MetricsEnabled + fido2MetricsAggregationEnabled).
Wait for (or trigger) an aggregation job to fire.

See the error in the FIDO2 server log:

io.jans.exception.ConfigurationException: ou=node is not configured in static configuration of AS (jansConfStatic).
at io.jans.service.cluster.ClusterNodeService.getClusterNodesLive(ClusterNodeService.java:137)
at io.jans.fido2.service.metric.Fido2MetricsAggregationScheduler.startPeriodicLockUpdates(Fido2MetricsAggregationScheduler.java:404)
at io.jans.fido2.service.metric.Fido2MetricsAggregationScheduler.initializeClusterLockUpdates(Fido2MetricsAggregationScheduler.java:147)
at io.jans.fido2.service.metric.Fido2MetricsAggregationScheduler.executeAggregationJob(Fido2MetricsAggregationScheduler.java:110)
at org.quartz.core.JobRunShell.run(JobRunShell.java:203)
...
Expected behavior

A single-node deployment (no ou=node configured) should run metrics aggregation in single-node mode without throwing or logging a ConfigurationException stack trace, emitting a clean INFO line like FIDO2 metrics aggregation in SINGLE-NODE mode (ou=node not configured). Genuine cluster deployments (with ou=node configured) should continue using distributed locking exactly as before.

Screenshots
N/A — server-side log output (stack trace shown above).

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Additional context

Component: jans-fido2 → Fido2MetricsAggregationScheduler / Fido2ClusterNodeService
Affected file: jans-fido2/server/src/main/java/io/jans/fido2/service/metric/Fido2MetricsAggregationScheduler.java
Fix applied in this change:
initializeClusterEnvironment() now checks getBaseClusterNodeDn(); if ou=node is blank it runs in single-node mode and never makes cluster calls, so the exception is never thrown.
startPeriodicLockUpdates() now logs a concise one-line warn (message only) instead of error with a full stack trace, since the single-node fallback already handles the condition.
No functional change: cluster mode behaves exactly as before; single-node mode produces the same aggregation result, just without the misleading stack trace.