* fix: inject-only slot contention, monitor events, and UA timer display
Per-peer slot contention for inject-only multi-hotspot: REPEAT and bridge
downlink respect each hotspot's busy slot instead of blocking the whole
MASTER. REPEAT monitor reports and companion TX fan-out are filtered when
the target peer would not accept the downlink.
Monitor topology remap reads MASTER STATUS via bootstrap callback and
suppresses OBP/companion voice events for peers with an active QSO on
another TG in the same slot. START,RX is emitted only on a new stream id.
UA TIMER=0 (legacy no-expiry): domain sentinel, topology omits infinite
ua_timer_min, SINGLE sessions store expires=0 instead of ~68-year offsets,
and export omits absurd expires_at values.
* feat: dynamic TG restore, OBP cross-slot downlink, and DB migration 005
- Export ua_multi_tgs in topology for monitor chip restore after server restart
- Defer OBP→HBP slot contention on inject-only proxies; clear other-slot SINGLE session on new TX
- Fix infinite UA timer persistence (expires_at NULL) and restore from DB (expires_at=0 sentinel)
- Push CONFIG to monitor after async dynamic-TG restore on RPTC
- Migration 005_peer_dynamic_tgs_expires_null (shared with adn-monitor)