Task: UI to Allow Mods/Admins to Batch-Create Runs/Leaderboards

[zysim]

What are you wanting to be added?

As part of MVP, we need to allow mods to migrate existing leaderboards over to our site as pain-free as possible. For this, we should create a page/some UI to allow this, with error handling and such.

The business logic will be handled in leaderboardsgg/leaderboard-backend#56

What might break?

Nothing should break on the frontend. It should only mess up the backend.

Relevant Issues

leaderboardsgg/leaderboard-backend#56: backend logic to handle batch creation of runs/leaderboards

[TheTedder]

not planned as of right now