As i understand it Valetudo is not actually firmware to control the robot. It is a “parasite” that makes the existing robot firmware belive it is connected to the cloud which is very different from actually controlling and navigating the robot. However, in terms of homeasistant integration it could be worth getting inspired.

For a control operating system ROS could be something to consider. When I used it 10 years ago the project was quite unstable since tools changed constantly and it was overly complicated to work with, but a lot of development has happened since so maybe worth considering. I wrote this before reading the article