Feature: better highlighting of fundraising feature

[eddy-geek]

There is an existing fundraising feature "Aider les acteurs locaux", see e.g. Mollans-sur-Ouvèze - Baume des Eyguiers

People want instead a more visible and customizable message (at least in a single language).

For now we agree to keep the hacky existing solution which is hardcoded in the UI at c2c_ui/src/js/get-fundraiser.js.

Exact placement to be filled later.

Raised during CA today.