Add Recursion Exercises

[JoshDevHub]

Complete the following REQUIRED checkboxes:

• [x] I have thoroughly read and understand The Odin Project Contributing Guide
• [x] The title of this issue follows the location for request: brief description of request format, e.g. Exercises: Add exercise on XYZ

The following checkbox is OPTIONAL:

• [x] I would like to be assigned this issue to work on it

---

1. Description of the Feature Request:

Adding new Recursion Exercises to bring them in house and provide good tests for our learners to develop against. There's a corresponding issue on the curriculum repo that also includes information about this change in the JavaScript path as well: https://github.com/TheOdinProject/curriculum/issues/27265

2. Acceptance Criteria: Need to add the following exercises under a new recursion/ directory. I will check these off as the PRs are approved. I will merge them after they have all been approved and everything is ready for our learners to work on.

• [x] #factorial | PR
• [x] #contains? | PR
• [ ] #total_integers | PR
• [ ] #permutations | PR
• [x] #pascal | PR
• [ ] #hanoi