[PB-4447]: refactor/create custom hooks to fetch products and initialize checkout

[xabg2]

Description

New custom hooks to initialize the checkout and fetch the products (price and coupon code).

Related Issues

Related Pull Requests

Checklist

• [x] Changes have been tested locally.
• [ ] Unit tests have been written or updated as necessary.
• [x] The code adheres to the repository's coding standards.
• [ ] Relevant documentation has been added or updated.
• [x] No new warnings or errors have been introduced.
• [x] SonarCloud issues have been reviewed and addressed.
• [ ] QA Passed

Testing Process

Additional Notes

There are more changes to do. They will be done in another PR.