It’s mentioned in the books, kopeng. I think it comes up in some of the repair scenes, but there’s such a jargon dump in many of them that it might slip by. Naomi is caressing some of it at one point, like she’s petting a cat. Which is not far off from how she sees the Roci.
I can think of two in the show, but one is right before Holden needs to tell Nagata something important, and the other is in the middle of a brain dump at Tycho station when the Roci is being diagnosed for repairs.
But the coloration in the window sure suggests spalling. I’m surprised the tempered glass did that much damage. That takes a lot of velocity. Which is probably why they aren’t thinking bird.