DRAFT: Refactor utils and tools, add first party source for ruff and set initial environmenet

[LucaRom]

Main update is a suggested refactoring of the tools folder and the utils.py file.

The vision is to promote modularity and future growth of GDL while avoiding a clogged utils.py file as we add different use cases and projects.

Distinction between tools and utils:

• utils : Modular and reusable generic functions that are as much of possible context-agnostic and could be used across any dataset, datamodule, project, etc.
• tools : Contains high-level components, wrappers and project/domain specific functions. (logging, schedulers, water extraction specific functions, etc.)

Refactoring details :

• utils.py is split into 2 new files under the utils folder (models.py and tensors.py)
• raster.py contains new generic functions that were created when working on the water extraction
• tools folder stays as is, minus the utils.py file

Other updates:

Smaller commits are also included in this PR:

• First party source was specified in the pyproject.toml file. This ensures that imports from the GDL-specific modules are recognized as first-party and are therefore grouped separately during auto-formatting.
• A first version of the environment.yml file was added as it is also needed for the github action on push.
• A dummy test was created to make the github actions on push pass.