Well, knowing how spoon isn't following the exact novel, we can only guess.
I think Claude will regain his memories on Athy's birthday like in the novel, but I have no idea as to how Claude will be healed. (in the novel, Lucas stabbed Claude with the world tree branch to heal him, but I think that's a bit too silly for spoon to follow).
Athy becomes pretty good with magic in the novel, but never really went into depth about it. Or Maybe I just don't remember the novel giving much detail about it, lol.
Seeing as spoon has a heart for Jeanette, I think she'll get her own happy ending in one way or another.