nextPublisherSequence read and rewrote <dataRoot>/runtime-presence-sequence at
mode 0600, which the next generation (a fresh DynamicUser uid in the shared
state group) cannot open. Odin compares publisher_sequence only within one
activation and Idunn mints a new activation per start, so PublisherSequence
derives it from the observation clock, never below the previous value plus
one, as Muninn does. openProviderHealthIdentity under
GAMECULT_IDUNN_RUNTIME_BUNDLE now refuses when the presence descriptor is
absent instead of enrolling an identity Idunn does not trust.
Adds the cross-generation test (root only) and the sequence, no-dataRoot and
missing-descriptor tests.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
