Debug-only perf instruments: the probes ?debug sessions add on top of the
always-on perf counters.
Installed from the standalone bootstrap's debug seed — BEFORE init() — so
a probe reading getPerf() during the first load (the window the perf gates
measure) sees them, and again from installDebugInterface for embedders
that turn on debug without the bootstrap. Every step is idempotent.
Debug-only perf instruments: the probes
?debugsessions add on top of the always-on perf counters.Installed from the standalone bootstrap's debug seed — BEFORE
init()— so a probe readinggetPerf()during the first load (the window the perf gates measure) sees them, and again frominstallDebugInterfacefor embedders that turn ondebugwithout the bootstrap. Every step is idempotent.