Refactor State Management to Use Zustand

[timDeHof]

To simplify and enhance our app's state management, we plan to integrate Zustand. The goal is to refactor our current state management solution to use Zustand, starting with a small, isolated part of the state and gradually expanding to other parts of the app.

Acceptance Criteria:

• Install and set up Zustand.
• Refactor a small, isolated part of the app's state to use Zustand.
• Gradually expand Zustand's usage to other parts of the app.
• Document the state management architecture and best practices.