| -- Make remoteJid nullable so unregistered drivers from groups | |
| -- can be created without a WhatsApp JID (they only have phone_number) | |
| ALTER TABLE public.customers ALTER COLUMN "remoteJid" DROP NOT NULL; | |
| -- Update unique constraint to allow NULL values (PostgreSQL allows multiple NULLs by default) | |
| -- No additional action needed since UNIQUE already permits multiple NULLs | |