feat: dockerize pixelrag serve engine

[Youcef3939]

this pull request introduces docker support for the project, enabling containerized development and deployment. the main changes include adding a multi-stage Dockerfile for building and running the application, a .dockerignore file to optimize build context, and a docker-compose.yml for orchestrating the service and persistent volumes

docker support and build optimization:

• added a multi-stage Dockerfile to build and run the application, installing all necessary system and python dependencies, copying source files, and setting up the runtime environment
• added a .dockerignore file to exclude unnecessary files and directories from the docker build context, improving build performance and reducing image size

service orchestration:

• added a docker-compose.yml file to define the pixelrag-api service, expose the application on port 8000, set environment variables, and mount persistent volumes for index and tiles data

issue #110

[vercel]

@Youcef3939 is attempting to deploy a commit to the andylizf's projects Team on Vercel.

A member of the Team first needs to authorize it.

[Youcef3939]

yo @andylizf, if you have some time can you kindly review the pr?