Refactor Data Fetching to Use TanStack Query

[timDeHof]

To improve our data fetching, caching, and synchronization processes, we aim to integrate TanStack Query (formerly React Query). This task involves refactoring our existing data fetching logic to use TanStack Query's hooks and features.

Acceptance Criteria:

• Install and configure TanStack Query.
• Refactor existing data fetching logic to use useQuery and useMutation.
• Ensure proper caching and invalidation of data.
• Document the changes and usage patterns for future reference.