Reexport API functions

[marcospassos]

Summary

This pull request removes the Content API utilities that have been moved to the plug-js library. For more information, see the corresponding PR on the plug-js project.

⚠️ This is a breaking change, as importing the specific function files will no longer work.

Blocked by croct-tech/plug-js#271

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings