Spencer Pratt finally had a chance to confront LA Mayor Karen Bass on the debate stage on Wednesday evening, delivering an impassioned performance that could change the shape of the race. The reality TV star and Palisades Fire victim channeled months of frustration with the city and the state into an effective effort at the Skirball Cultural Center, in a debate moderated by NBC 4 and Telemundo 52. NBCLA The moderators tried to restrain him from the beginning, nervously warning against “name-calling” and then scolding him when he called Bass a “liar”, after she said some of his claims were “inaccurate.” They treated him like the beggar at the feast, the commoner at the royal table, like he didn’t belong. It didn’t matter. Pratt was the strongest personality on the stage. And — in the biggest surprise at all — he looked solid, like a big-city mayor, with expertise beyond the devastating fire that motivated him to run. On the left, Bass also took hits from socialist City Council member Nithya Raman .…