Consolidate the operator entry point for planning, storage classes and
EC:0 consequences, expansion, rebalance, decommission, heal, drive
replacement, restart recovery, and the rc CLI mapping. Every claim was
checked against the current handlers, storage-class validation, quorum
arithmetic, and the rustfs/cli admin reference; the runbook links the
normative contracts instead of restating them.
Refs rustfs/backlog#2607, rustfs/backlog#2608
Chris