fix:Adds quantity selection and improved cart indicators

[marcramser]

• Adds quantity selection and improved cart indicators
• Shows the correct quantity of each item already in the cart on both grid and list views.
• Adds an input field with plus/minus buttons to select quantity before adding to cart.
• Updates the cart logic to handle selected quantities correctly.

[marcramser]

I’m closing this PR for now due to the lack of feedback, review, or any response.

@rmehta (sorry for tagging you, but I feel like someone at Frappe needs to hear this)

It’s unclear whether this project is still actively maintained. If not, it would be very helpful if that were documented somewhere. From the outside, several repositories in the Frappe organization appear "Zombie-like", it's super hard to assess which apps are safe to rely on in a professional environment and which are just existing.

A public roadmap or a clear indication of long-term maintenance intentions would greatly improve confidence for contributors and users alike.

[rmehta]

There is a new builder based front end that is in the works, but no excuse for not notifying people raising PRs

cc @surajshetty3416 @stravo1