- setCwd now updates the saved __omp_session__ stack entry so a deferred
cross-runtime setCwd is visible to the runtime's next run (review should-fix)
- JsRuntime installation asserts realm ownership before mutating globals;
a first init during another runtime's live run fails via init-failed
instead of clobbering the active run's globals
- cmux runCmuxCode marks the armed cancel rejection as handled so a sync
setup throw under an already-aborted signal cannot become an unhandled
rejection (review P2)
- credited #4907 in the changelog entry
When the JS eval worker falls back to the in-process inline path, concurrent
JsRuntime instances share one realm. setCwd used to throw on exclusive-owner
conflicts, and the microtask delivery path turned that into a fatal
unhandledRejection that postmortem exited on. Stamp local cwd without
stealing the active realm, report init failures over the worker protocol,
and cover process survival with in-process and child-process regressions.