ALTER TABLE `novel_sources`
  ADD COLUMN `ai_provider_code` VARCHAR(100) NULL,
  ADD COLUMN `ai_model_name` VARCHAR(160) NULL,
  ADD COLUMN `ai_cost_estimate` DECIMAL(12, 4) NULL,
  ADD COLUMN `ai_cost_actual` DECIMAL(12, 4) NULL,
  ADD INDEX `ns_ai_provider_idx` (`ai_provider_code`);

ALTER TABLE `novel_chapters`
  ADD COLUMN `ai_provider_code` VARCHAR(100) NULL,
  ADD COLUMN `ai_model_name` VARCHAR(160) NULL,
  ADD COLUMN `ai_cost_estimate` DECIMAL(12, 4) NULL,
  ADD COLUMN `ai_cost_actual` DECIMAL(12, 4) NULL,
  ADD INDEX `nc_ai_provider_idx` (`ai_provider_code`);