docs(leaderboard): Design the leaderboard for showcasing benchmark data

[christian-pinto]

Description

The design of the leaderboard must answer the below questions, providing details for driving the actual implementation

• How to visually present the data to users.
• Can model owners modify their leaderboard view?
• How do we decide which data goes in the leaderboard? How often (e.g., every release) and which data
• Where do we host the leaderboard and how does it access the benchmarking data.
• Do we have a leaderboard per Model? Comparing the same across releases or do we also compare models over common metrics?

Outcome

A design document clearly describing the details of how to implement the leaderboard. To be committed to the repository.