A naive ISO timestamp (e.g. 2026-06-22T20:07:00) was anchored to the
server's local timezone via dt.astimezone(), but the due-check
(get_due_jobs -> _hermes_now()) runs in the CONFIGURED Hermes timezone.
When the two diverge (cloud host on UTC with a different timezone: set,
or vice-versa) the stored instant lands hours off the user's wall-clock
intent, so one-shots never become due and recurring jobs fire at the
wrong time. The ticker stays healthy (heartbeat + success markers fresh)
because every tick finds nothing due, matching the silent no-fire in #51021.
Anchor naive timestamps to _hermes_now().tzinfo so '20:07' means 20:07 on
the same clock the scheduler checks against. The legacy _ensure_aware path
still treats already-stored naive values as server-local for back-compat.
Fixes#51021
d93d0aee83