As I type this, our cat Pyewacket is chasing Dawn, our little Netherland Dwarf, all over the house. At speed. And when they’re done, they’ll reverse roles, and Dawn will then chase Pye all over the house again. And when they’re done, they’ll both flop down on the ground, cuddle up together, and nap. Occasionally they even groom each other. Watching a 2 pound bunny chase a 10 pound cat is pretty darn funny.
I worried about the same thing. Pye will stalk and swat at Dawn from time to time, but no claws and it’s normal behavior. Dawn, if she doesn’t feel like playing, will growl and punch with her front feet. Again, all normal.
Basically, if your cat was going to actually attack your bun, it would have happened in the beginning, but not now. They’ve bonded, and it’s all just play.
I was nervous about leaving the buns loose at night (My rabbits have free roaming rights at night) with the cats loose at the same time, but nope. No problems.