Refactor Product improvements into a button (per mock)

[teolemon]

What

• Refactor the snackbar Product improvements into a discreet button on the product page, per mocks
  • d41a0b1
  • The buttons have to be ventilated across panels (if Nutri-Score, on the health panel, if Eco-Score on the environment panel, if Ingredients on the Health panel). For the summary card, we need to be inclusive: "Add a category for Eco-Score and Nutri-Score".
• On button click, let's open as a first the Web View edit mode (and we'll plug the merged novelties from Implement improved contribution flow in app #505 a bit later)

Mockup

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[jasmeet0817]

@stephanegigandet how should we do this one ? Should BE tell the client what improvement can be done for the product in a knowledge panel ? Or should the client figure it out on it's own.