[INTW26] Create Interview Delegations Model + Migration File

[chene0]

Notion ticket link

Create Interview Delegations Model + Migration File

Implementation description

• Created a model file for new table interview_delegations with columns and relationships according to the TDD.
• Created a DTO for the new table
• Created an array for interview conflict options, set column interviewHasConflict in interview_delegations to an enum of these options

Steps to test

1. Run the command docker exec recruitment_tools_backend node migrate up
2. Verify that the new interview_delegations table created in the db matches the schema in the TDD

What should reviewers focus on?

• Correct types and foreign key relationships

Checklist

• My PR name is descriptive and in imperative tense
• My commit messages are descriptive and in imperative tense. My commits are atomic and trivial commits are squashed or fixup'd into non-trivial commits
• I have run the appropriate linter(s)
• I have requested a review from the PL, as well as other devs who have background knowledge on this PR or who will be building on top of this PR