MarmotInboundProcessor and CommitOrdering.EpochCommitTracker used
`synchronized(lock) { ... }`, which is a JVM-only intrinsic. Compiling
the quartz KMP module for iosSimulatorArm64 (and other non-JVM targets)
failed with "Unresolved reference 'synchronized'".
Switch to kotlinx.coroutines.sync.Mutex + withLock, matching the pattern
already used in MlsGroupManager. EpochCommitTracker's public API becomes
suspend — update the MarmotInboundProcessor delegates (pendingCommitGroupEpochs,
clearPendingCommits) and wrap the commonTest cases in runTest. The
MarmotPipelineTest jvmAndroid tests already run inside runBlocking, so
no changes needed there.
Also reshape the processGroupEvent dedup check to hoist the "already
processed?" read out of the lock block so the early return isn't a
non-local return from the withLock lambda.
Claude
552ff7a2ce