Add backend configuration and Docker setup for Bun application

Commit notes

- Introduced a new `Dockerfile` for building and running the Bun application, including multi-stage builds for dependencies and production runtime. - Created `docker-compose.yml` to define services for PostgreSQL, Redis, and MinIO, with health checks and environment configurations for each service. - Added `.dockerignore` to exclude unnecessary files from the Docker context, improving build efficiency and security. - Included a `pnpm-lock.yaml` file for dependency management, ensuring consistent installations across environments.

This commit establishes a robust backend infrastructure for the Bun application, facilitating development and deployment through containerization.