Refactor: Transition from Context API to Reducers

[sayyidmarvanvt]

This pull request introduces a significant refactor of the state management approach in the application. The following changes have been made:

1. New File Added:

   • utils/reducer/reducer.utils.js: This file contains utility functions to manage state updates using reducers.

2. Updated Context Files:

   • user.context.js: Refactored to utilize the reducer pattern for managing user authentication state.
   • categories.context.js: Updated to use reducers for handling category-related state.
   • cart.context.js: Changed to employ a reducer for cart state management, allowing for better scalability and maintainability.

3. Purpose of Changes:

• Improve the scalability of the state management logic.
• Enhance code readability and maintainability by utilizing the reducer pattern.
• Prepare the codebase for future features that may require more complex state management.