Simplify dev environment: drop ETL, cleanup Makefile, improve README

[MateoLostanlen]

Summary

This PR removes the unused ETL service and simplifies the developer workflow.

Changes

• Removed ETL

  • Dropped etl_scripts service from docker-compose.yml
  • Removed run-etl and ETL references from Makefile

• Makefile

  • Added init target for .env creation (run once)
  • Simplified run (frontend + tools) and run-all (frontend + tools + engine)
  • Reordered and cleaned up targets for clarity

• README

  • Added a Quick Start section with minimal commands:

    make init
    make build
    make run

  • Updated instructions to send alerts via Jupyter notebooks and view them in the frontend or API

  • Documented services, access URLs, and credentials

  • Removed all ETL references

[fe51]

Thanks a lot for the PR, find it more clear now.

I think I will do one more iteration of the readme, but for sure, it's already better than before.

I just made a few comments

[fe51]

Thanks for the udpates !
LGTM !