mds: aggregate and expose subvolume metrics

mds: aggregate and expose subvolume metrics

rank0 periodically receives subvolume metrics from other MDS instances
and aggregate subvolume metrics using sliding window.
The MetricsAggregator exposes PerfCounters and PerfQueries for these
metrics.

Resolves: ISCE-2037

Fixes: https://tracker.ceph.com/issues/68931
Signed-off-by: Igor Golikov <igolikov@ibm.com>
(cherry picked from commit a49ba9d27ab93fe3466822d8865c6112eea86c09)
(cherry picked from commit bb49fe739f5c9b83439f02449c8f3df3e26bd9cc)

 Conflicts:
	src/mds/MDSPerfMetricTypes.h

Adjust decoding version since CopyIoSizesMetric is present in the branch.