Feature Request: Auto fill userfields from barcode

[EnochPrime]

Background

Products are intended to be general items such as 'Milk'. Each product can have multiple barcodes. This allows multiple real world products to be used or substituted in recipes and can provide easy to manage household inventory.

Barcodes are associated with a specific real world product and are unique to brand, flavor, size, etc. To date barcodes can have unique QU, amount, store, and note.

Grocy provides a way for users to extend products, barcodes, etc. with additional data via userfields.

When a user uses a barcode lookup on the purchase or inventory forms the value of the barcode product, QU, amount, and note are automatically populated into the form. However nothing happens with userfields.

Request

Upon using a barcode lookup for purchase or inventory automatically populate userfields with the corresponding product_barcode userfield. This expands upon the work from #2193.

Justification

While there is already a means to automatically provide custom barcode data to a stock entry via the note field this would allow for much greater flexibility for the user. Each userfield would be customizable and can be displayed on various tables as desired.

[berrnd]

This would practically mean that all defined Userfields for the entity stock and product_barcodes need to be exactly the same.

[EnochPrime]

This would practically mean that all defined Userfields for the entity stock and product_barcodes need to be exactly the same.

The Userfields names between stock and product_barcodes would need to match for auto fill to occur. I was thinking this would be on the user to setup and synchronize and there would not be a requirement for all Userfields to match.