My adviser wants to be the first author
It isn't a good career move to counter your advisor in things like this. You need him to sign your thesis (already done) and to write you a good letter of recommendation - maybe still to come. If you anger him, whether rightly or wrongly, it will be you that pays the price. 

As I said in a comment, this kind of "authorship" is common, accepted, and perfectly natural in some fields, even if it is a bit stupid. 

Having joint authorship with a professor can actually be a help to your career, even if he takes first authorship. Some people will just assume that he did all of the work (no matter the order of authorship), carrying you along. Others will just assume that you did all the work and he is first author by courtesy.

This is something you can't control.

But a publication with your name on it anywhere is a plus for your career. 

If you want to fight a system that you think is stupid, wait until you have some power and standing in academia to back you up. Otherwise you get squashed before you have a chance to fly. 

Work with him and get a good letter. 

I realize this isn't the answer you wanted to read. But think long term, not the short.