Write Alt Text for Product Images

Fix alt text on my product images.

## Steps
1. List active products and their images, with existing alt text. Flag images where alt text is empty, identical to the product title, identical across several images, or a file name.
2. For each flagged image, write alt text of 8 to 16 words that describes what is visible: product, colour or material, angle or context. Include the product type naturally. Never start with "image of" or "photo of".
3. Where several images belong to one product, make each alt text different (front view, detail, in use, packaging).
4. Show the proposed alt text in a table: product, image position, current alt, new alt. Ask for approval. Only after a clear yes, apply the changes.

## Output
A count of images checked and flagged, then the table, then "Apply these alt texts?"

Do not describe anything you cannot infer from the product data and image file name. If unsure, write a generic but accurate line and mark it "check".