Add Docker Compose Setup and Improve Local Development Documentation

[StefanRoesch]

Add Docker Compose Setup and Improve Local Development Documentation

Summary

This PR introduces a docker-compose.yml file and updates the README.md to make local development setup easier and more accessible. It also clarifies the steps performed by the mix setup alias.

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Changes

• Added docker-compose.yml:

  • Provides services for Postgres (with pgvector) and Ollama.
  • Includes persistent volumes and optional GPU support (commented).
  • Automates pulling required Ollama models for convenience.

• Updated README.md:

  • Added a section explaining how to use Docker Compose for local development.
  • Clarified that Docker must be installed to use this method.
  • Detailed the steps performed by the mix setup alias for better onboarding.
  • Improved overall clarity for new contributors.

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Motivation

• Simplifies onboarding for new contributors and users.
• Reduces the need for manual installation of dependencies.
• Makes it easier to get a working development environment with a single command.

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How to Test

1. Ensure you have Docker installed.
2. Run:

   docker compose up -d

3. Follow the updated README instructions to start the Phoenix server and verify that both Postgres and Ollama are running as expected.

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Notes

• The Docker Compose setup pulls required Ollama models automatically for convenience.
• GPU support is available by uncommenting the relevant lines in the compose file.

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Feedback and suggestions are welcome!