The Warriors saw flashes of what new addition Kristaps Porziis can bring — but also saw how far they still have to go.Porziis made his Golden State debut in Thursday’s 121-110 loss to the Boston Celtics, finishing with 12 points in 17 minutes. While he showed flashes, he also displayed some rust after missing the last 43 days due to injury management and illness.That reality is shaping how Steve Kerr plans to use him moving forward.In an interview with 95.7 The Game’s “Willard & Dibs,” Kerr explained the expectation is for Porziis’ minutes to increase, but emphasized the process will remain gradual.“Hopefully the minutes go up, but it’s all really kind of day to day,” Kerr said. “Our training staff will determine that. It was a good starting point last night — he felt good after the game, we had a good practice today and Kristaps took part in everything.”Porziis’ debut reflected both promise and limitations. He appeared more comfortable as the game went on, but Golden State quickly fell behind during his first stint as Boston seized control with a decisive second-quarter run.It’s a reminder of...