I would like to know which packages/snaps does Bootstrap command installs on the Controller.
Is it possible to manually bootstrap a controller? For example, to bootstrap a MAAS cloud controller (install and configure packages manually).
Or to edit the scripts that are executed on the controller.
Juju will apt install these packages when creating a controller:
You can start with an existing machine and have Juju bootstrap that machine as a controller. There’s some doc here
You can customise instances further by using the cloud-init feature