feat(iOS): background-size, position and repeat styles (#52283)

Summary:
This PR adds support for background size, position and repeat styles. It follows the [CSS](https://www.w3.org/TR/css-backgrounds-3/#backgrounds) spec. Currently we default to `background-origin: padding-box` and `background-clip : border-box` to match the web's behavior. We can introduce these styles later. I have split the PR intro three parts for review. This PR includes iOS only changes. I wanted to introduce one style at a time, but CSS spec is such that size, position and repeat are intertwined.

## Changelog:
[IOS][ADDED] - Background size, position and repeat styles.
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Pull Request resolved: https://github.com/facebook/react-native/pull/52283

Test Plan:
Merge the [JS](https://github.com/facebook/react-native/pull/52284) PR, run `pod install` and test RNTester example, it includes `BackgroundImageExample`. I have also added testcases for syntax parsing in JS.

https://github.com/user-attachments/assets/b7192fdf-52ba-4eb0-a1be-d47c72d87e92

Reviewed By: joevilches

Differential Revision: D82993888

Pulled By: jorge-cab

fbshipit-source-id: af545acaf4b9d116b5905f912c494d2e77324380