d3be5f0527
The gauge test polls baseline+1, but the process-global gauge's baseline is captured once: a parallel class's streams closing after capture lowers the gauge below baseline+1 forever. Survey confirmed only SiteStreamGrpcServerTests and CleanupVerificationTests drive the real SubscribeInstance handler that moves the counter; both now share the SiteStreamSubscriberGauge collection (row-96 pattern). 4/4 full-suite runs green, durations unchanged.