UpdateServerConfig was at 31; SonarCloud threshold is 20. The deep
nesting came from wrapping the whole body in the mgmtCacheResolver
nil-check and stacking five for-loops + conditionals inside it.
Invert to an early return when the resolver is nil, then split the
remaining work into two focused helpers:
- registerMgmtCacheHandlers: handler-chain wiring (pool-root
subdomain wrapper + exact-match registration) with the toZone-
canonicalized membership check.
- reconcileMgmtPoolRoots: extraDomains refcounting against the
current pool-root set, plus the mgmtPoolRoots tracking map.
Pure refactor — behaviour is identical.
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