Add shipping, tax and fee lines to refund response for better information in refund REST API.

[vedanshujain]

All Submissions:

• Have you followed the WooCommerce Contributing guideline?
• Does your code follow the WordPress' coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

This adds shipping, tax, and fee lines to refund response in API V2 and V3.

Closes #27566

How to test the changes in this Pull Request:

1. Create an order with shipping, tax and fee lines.
2. Refund these items.
3. Fetch the order refunds in API V2 or V3 using /orders/{order_id}/refunds endpoint.
4. Verify that fee_lines, shipping_lines and tax_lines are present.

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully run tests with your changes locally?

Changelog entry

Enhancement - Add shipping, tax and fee lines to refund response for better information in refund REST API.

[vedanshujain]

• This also needs a PR to update the documentation to reflect this change, and also to clarify how to do itemized returns from the API.

[roykho]

Tested well, LGTM!