feat: add Playlist Remix Engine lab prototype

[VuBui217]

Checklist:

• [ x] I have read freeCodeCamp's contribution guidelines.
• [ x] My pull request has a descriptive title (not a vague title like Update index.md)

Reference issue #64113

This is a prototype for a new lab for the Full Stack Certification Curriculum, as part of Naomi's sprints group for November-December. This PR adds the full prototype for the Playlist Remix Engine lab as requested in issue freeCodeCamp/freeCodeCamp#64113

[jdwilkin4]

It looks like there are a lot of concepts used like set, map, etc that might not be taught yet.
Please double check on discord on where this lab is supposed to go in the curriculum order because it is possible you will need to refactor some of this if certain concepts haven't been taught yet.

[VuBui217]

Thank you for your feedback! I'll double check on it

[VuBui217]

Hi @jdwilkin4, I have refactored the prototype to align with the curriculum. Please let me know if any further adjustments are needed.

[jdwilkin4]

I left some comments on the solution and user stories.

But I also noticed that none of the function are actually being used anywhere. We want campers to build out a lab where all functions are being used at some point.

So the user stories and final solution will need to be updated to reflect that.

[jdwilkin4]

Push up a couple of commits to speed up the review process.

It looks like we are good to go with this.
There will proabbly be some tweaks to the user stories in the next review stage when this is added to the main repo.

But this is ready to start being added to the main repo with tests 👍🏾

[VuBui217]

Thank you @jdwilkin4! I'll process to the next steps.