NEW image command for product imports

Product imports now support a NEW image command that adds media only when products have no existing images, giving you more control over how media is handled during imports.

🚀 What’s New

• NEW image command – adds media only if the product has no existing images, skipping media processing entirely for products that already have media.

🔧 Improvements

• Image command validation – updated error messages to include all valid commands (MERGE, REPLACE, NEW, DELETE, IGNORE).
• Faster imports – products with existing media skip unnecessary processing when using the NEW command.