Migrate prototype code

This PR is migrating the prototype code from TomoArtifactBenchPy to this repo, including:

• all prototype source files
• all prototype unit tests
• new unit test files
• new synthetic data for development and testing
• new example notebook for demo

Testing instructions

• On a GPU node, create a conda environment using the new environment.yml file
• Perform editable install with pip install -e .
• At the root of the repo, run all unit test with pytest -v tests/unit, and all tests should be passing
• Start the notebook notebooks/example.ipynb, and step through the notebook, and you should be able to go through all cells and get the following results.

EWM Story 4914

Note: the added files are just prototype, and we clearly need to improve the denoising quality further to match the close source one.