[TASK] Improve installation procedure so that scripts *and* LSPs can access the `src/soundade` files

Currently we use conda for installing all of the library dependencies, but we use a `pyproject.toml` file to make our own source files available to the run scripts at runtime.

This is both concenptually awkward and confuses language servers that provide code help in development environments (code inspeciton, dependency following etc).

I currently work around this by having a virtual environment where I keep our source installled `pip install ` but that means that my LSP uses the virtual environment's source files instead of the ones im editing. Again, awkward.

we should probably just load the src files using `sys.path.append` in each of the scripts but we need to take care to do that in a way that works for different runners (local, docker, singularity)