Refactor UI components

[X1nto]

• [x] Separate stateless and stateful composables
• [x] Move ViewModel controlling from HomeScreen to individual panels
  • This removes the need for HomeScreen to call load() functions when data changes. Instead, ViewModels observe data changes themselves and update the UI accordingly. This should ensure that all data is updated properly.
• [ ] Refactor navigation
• [x] Get rid of BasePersistenceViewModel
• [ ] Refactor smaller components, such as messages, etc.