Haven't heard anything about a series bible, just interviews.

This one mentions that half of all life includes animals.

I do need to confirm something about the outcome of Infinity War, and apologies if you’ve addressed this – the end of Ant-Man and the Wasp led to conversations. Are half the animals dead? Are half of the horses gone? Half of the ants?

Yes! Yes. All life.
This one has a bit more.

Erik Sommers: You spend a lot of time in a room with the team just talking about all this stuff. There were some things we definitely talked about a lot. “Okay, let’s say you were in an airplane and you blipped and then you come back, but the airplane is not in the same place anymore, so do you just blip back in the sky? And then is it half of all life? Does that mean, like, cats and animals? And what happens to the bees? They’re already having so much trouble, the bees.” So we got bogged down in the nitty-gritty.

What answer did Marvel give for the airplane question?

McKenna: We were told that when Bruce [Banner] brings everyone back that he accounted for that, that was part of his wish. Everyone came back safe and sound. We don’t have to worry about people falling out of the skies.

And the bees?

McKenna: The bees were fine too. They all came right back to their hives.

But animals did disappear during the blip.

McKenna: All life forms. Even down to the bacteria in your digestive system. We were wondering if we could make a whole plot point about people’s digestive systems that were really screwed up.