Explain the plot of the game (Stray)

there was a plague, people built a city underground and made a hermetic dome, for some reason they all died (perhaps they brought it inside), only the robots that worked for them remained, they adopted some of the habits of their owners, built a caste system, for example the guards still had a directive to guard the passage to the surface, because it was dangerous there, although they themselves did not know why, but there were algorithms in their program. remained original. Well, the locusts that devoured everything in a row were garbage collectors that evolved and began to process everything in general. The only moment who controlled them, in frames, when the cat runs away from them and dozens of eyes are watching you, it looks like they were in command, some kind of collective mind. In short, many questions remain unanswered. Perhaps there will be a second part, according to the last frame,

fundamentalist
, only the robots that worked for them remained - partly true, but in fact, when they realized that they were dying, all people transferred their consciousness into these robots.
These are people, just with the body of robots

fundamentalist
I really hope that they hinted at the end that the B-12 is alive :'(