Handle l10n_state

[lolli42]

There is currently zero code to check l10n_state - that funny json field that declares how single field translations are handled.

Some related core issues:
https://review.typo3.org/c/Packages/TYPO3.CMS/+/80518
https://review.typo3.org/c/Packages/TYPO3.CMS/+/80517