AnnouncementClock

announcementClock() for many times against one now, as `list` writes a time for each receipt (§KA-R-5).

In the namespace kiln::remote. Declared in src/libs/libkiln/kiln/remote/Announcements.hpp.

Detailed description

The zone's offset is read once. A time between the zone's transitions around now has that offset exactly, and its fields come from the UTC time plus the offset, with no conversion and no locale format. A time outside them, or a zone with no transitions, takes announcementClock()'s full conversion.