Answer
What is the difference between crowdfunding and a donation?
Short answer
A donation buys you nothing and expects nothing back. A reward pledge obliges the creator to deliver the thing they described. Portuguese law treats them as two separate modalities for exactly that reason.
If you give to a charity, the transaction is finished the moment the money leaves. You may get a thank-you, but nobody owes you anything and the charity has no delivery obligation to you personally.
A reward pledge is not that. The creator has committed to producing the product or service being funded, and receiving your money is what makes that commitment binding. You are much closer to a customer of something that does not exist yet than to a donor.
This is why the two are named separately in Lei n.º 102/2015, and why it matters which one a platform is running. A site that collects reward pledges while describing them as donations is understating what its creators owe, and a backer reading it would misjudge what they are entitled to if delivery never happens.
CoFunders is reward crowdfunding only. Every campaign has a creator with a stated obligation, and no campaign on the platform is a donation with nothing owed in return.