Non-functional codebase improvements

[Omrigan]

Problem description / Motivation

There are small-scale non-functional changes/tech-debt we occasionally want to make here and there, but they do not have enough priority to deserve a separate issue. Feel free to add more.

Not sure it is the best way to track that, but I realized I keep a bunch of those in the head and needed to dump them somewhere.

Feature idea(s) / DoD

This issue doesn't have a DoD.

Ideas / Inbox

• [ ] Check if we can rely on panic less
• [ ] Outdated/unmaintained dependencies cleanup

### Tasks
- [x] Use `ptr[T](obj T) *T` everywhere
- [x] Rename VirtualMachine to VM in neonvm-controller
- [ ] Replace ad-hoc workgroups with taskgroup from #922
- [ ] [Move sender threads to a taskgroup](https://github.com/neondatabase/autoscaling/pull/922#discussion_r1641972650)
- [ ] lint for the very long lines (e. g. https://github.com/neondatabase/autoscaling/pull/983#discussion_r1669831746)
- [ ] Use consistent name when importing github.com/neondatabase/autoscaling/neonvm/apis/neonvm/v1