X_TEST_ISLAND_STATE_CLOCK_INVALID
Means
an island state manifest pins a clock that is not pinnable
Typical cause
timeZone is not an IANA zone Intl knows, or now carries no explicit offset. A harness that freezes the instant and leaves the ZONE ambient renders every date in the host machine's, so one state photographs differently on two machines
Fix
write timeZone: 'UTC' and now: '2026-01-01T00:00:00.000Z' — an ISO instant ending in Z or an offset