fix: Correct roomuserid_lastnotificationread table alias

roomuserid_lastnotificationread was mapped to userroomid_highlightcount
instead of its own table, so last_notification_read() read the highlight
count and reset_notification_counts clobbered the highlight table when
setting a read marker. Add the missing table definition and fix the alias.

src/database/maps.rs

@@ -478,6 +478,10 @@ pub(super) static MAPS: &[Descriptor] = &[
 		name: "logintoken_expiresatuserid",
 		..descriptor::RANDOM_SMALL
 	},
+	Descriptor {
+		name: "roomuserid_lastnotificationread",
+		..descriptor::RANDOM
+	},
 	Descriptor {
 		name: "userroomid_highlightcount",
 		..descriptor::RANDOM