H2C / H2D AMS-HT units report ams_id 128+ (one ams_id per unit, single
tray), but spoolman_slot_assignments.ck_ams_id_range only admitted 0-7
and 255. Every attempt to link a Spoolman spool to an AMS-HT slot died
with `CHECK constraint failed: ck_ams_id_range`. The internal
spool_assignment table has no such constraint and works fine.
Widen the formula to (0-7) OR (128-191) OR 255 in the model, the
CREATE TABLE DDL, and an idempotent in-place migration for existing
installs (Postgres: DROP/ADD CONSTRAINT; SQLite: detect stale formula
in sqlite_master, rebuild via _v2 rename pattern).