evroon/bracket: Selfhosted tournament system

Bracket is a self-hosted tournament system designed for easy use, leveraging async Python with FastAPI for the backend and Next.js with Mantine for the frontend. It supports various tournament formats such as single elimination, round-robin, and swiss, and allows for dynamic scheduling and management of tournaments and teams. The system can be run using Docker or independently with pipenv and yarn, and is configured using .env files or environment variables.