HDDS-15413. Recon and SCM Container Sync Metrics addition.

[devmadhuu]

What changes were proposed in this pull request?

This PR extends ReconScmContainerSyncMetrics to expose per-state metrics for the four actively reconciled container states:

• OPEN
• QUASI_CLOSED
• CLOSED
• DELETED

For each state, Recon now reports:

• Last sync-pass duration in milliseconds.
• Last pre-sync observed container-count drift, computed as SCM count - Recon count.

The existing overall targeted sync metrics remain unchanged:

• targetedSyncStatus
• lastTargetedSyncDurationMs

Why are the changes needed?

Recon periodically syncs container state from SCM, every 6 hours by default. Before this change, metrics only showed the overall targeted sync status and total duration. Admins could not tell:

• Which state pass took time.
• Whether the latest cycle observed count drift for a specific state.
• Whether SCM had more or fewer containers than Recon for a given reconciled state.

The new metrics make this visible in Hadoop metrics and downstream Prometheus time-series data.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-15413

How was this patch tested?

Ran the below tests:

TestReconStorageContainerSyncHelper, TestReconScmContainerSyncMetrics