[rooms] remove friendlyname

apps/rooms/migrations/0017_drop_friendly_name.sql

@@ -0,0 +1,12 @@
+-- Retire `FriendlyName` from the room blob.
+--
+-- The rename route (PUT /rooms/:id/name) briefly wrote `FriendlyName` alongside `Name`,
+-- and every read defaulted it to `Name`. Neither exists any more: this server serves no
+-- display name apart from the unique `Name`, and a stored value would otherwise survive in
+-- the blob forever (`json_set` on rename is gone, so nothing would ever update it again).
+--
+-- Strip the key from every room that carries one. `json_remove` on a blob without the key
+-- is a no-op, so the WHERE only spares the rows that need no rewrite.
+UPDATE room
+SET data = json_remove(data, '$.FriendlyName')
+WHERE json_type(data, '$.FriendlyName') IS NOT NULL;