Create TanStack Query hooks for categories

[RossCabrera]

Overview

Create custom React Query (TanStack Query) hooks for categories management
with caching and optimistic updates.

Hooks to Create

useCategories()

• Fetches all categories for user
• Caches data
• Refetches on window focus
• Returns: { data, isLoading, error }

useCreateCategory()

• Mutation for creating category
• Returns: { mutate, isPending, error }
• Invalidates categories list

useUpdateCategory(id)

• Mutation for updating category
• Optimistic update
• Returns: { mutate, isPending, error }

useDeleteCategory(id)

• Mutation for deleting category
• Handles cascade (sets notes.category to NULL)
• Returns: { mutate, isPending, error }

Acceptance Criteria

• Hooks use TanStack Query
• Data cached automatically
• Refetching works
• Optimistic updates work
• Error handling works
• Mutations invalidate cache
• Deleting category handled
• Works with axios interceptors
• TypeScript support

Related Issues

• Depends on: Create Axios instance with JWT interceptors #12 , Build Category ViewSet with endpoints #19
• Blocks: Build note grid/card view #23, Add loading skeletons for UX #25, Set up drf-spectacular for Swagger docs #26