Google merchant feed optimizer

This checker reads Google's published product data requirements and applies a fix only when there is exactly one right answer, and every fix it makes is logged. It deliberately does not rewrite titles, invent brands, or repair GTINs that fail their check digit, because a guessed value is worse than a reported gap. It also stays local: no URL is fetched, no image is opened, and nothing is uploaded, so it cannot confirm that a link resolves or that an image renders. Comma decimals stay ambiguous and are reported, never rewritten. Export the corrected feed and upload it in Merchant Center yourself.