-- Step 31: Expand sessionCustomers.lang to support all dine-in languages
--
-- Previously lang was enum('cn','en','jp','kr'), limiting customers to only 4 languages.
-- The dine-in app now supports 25 languages (bg, cn, cz, de, dk, en, es, fi, fr, gr,
-- hr, hu, it, jp, kr, nl, no, pl, pt, ro, ru, se, sk, tr, ua).
-- Changed to varchar(2) so new languages can be added without future schema changes.
-- The PHP allow-list in session-handlers.php remains the source of truth for valid codes.

ALTER TABLE `sessionCustomers`
  MODIFY COLUMN `lang` varchar(2) NOT NULL DEFAULT 'en';