Invariant test for the #103489 salvage: a profile gateway and the root
gateway resolve the same hosted-room coordination file at the install
root, and that file is never the root SessionDB (`state.db`). Every
profile gateway starts the hosted-room worker unconditionally, so the
old mapping made each profile process a long-lived writer on the master
session store — the simultaneous-restart corruption in #102120 and the
main offender in the #103339 / #103490 fleet reports.
Also: WAL-fallback labels say `shared-state.db`, and test fakes take the
store path from `default_db_path()` instead of hardcoding `state.db`.
Reported-by: #102120#103339 (@RChina) #103490
Refs #102120#103339#103490
Teknium
d41e906598