Potentially breaking: Plain JSON arrays and tuples in the return types of
.toJSON(), useStorage() selectors, and
getStorageDocument(roomId, "json") are now readonly, which is consistent
with all other values these APIs return.
Add a hasThreads query filter to getRooms() and iterRooms(). Use true
or false to filter rooms with or without threads, or "unresolved" or
"resolved" to filter by thread state.