Partition messages into a byte-stable prefix and a volatile tail.
The prefix is the maximal contiguous leading run for which isStable returns true.
The moment isStable returns false, that message and everything after it are volatile —
even a later message that would itself be "stable", because once the leading run is
broken the provider's cached prefix is already lost from that point.
Pure and side-effect-free: the input array is not mutated; the returned arrays are
shallow slices of it.
Partition
messagesinto a byte-stable prefix and a volatile tail.The prefix is the maximal contiguous leading run for which
isStablereturns true. The momentisStablereturns false, that message and everything after it are volatile — even a later message that would itself be "stable", because once the leading run is broken the provider's cached prefix is already lost from that point.Pure and side-effect-free: the input array is not mutated; the returned arrays are shallow slices of it.