[feat] support user-provided base models

[danielgafni]

For reviewers

• I used AI and thorougly reviewed every code/docs change

Description of the change

Add a new configuration option: extra_bases. This allows extending the default list (pydantic.BaseModel, pydantic.main.BaseModel) with third-party base pydantic classes.

Relevant resources

Resolve #41, #14, #27

[danielgafni]

A few things:

1. I've run ruff on my files and looks like it introduced a few minor formatting changes. Seems like ruff isn't enforced on the repo?
2. I've tested this code on my dagster-ray lib, it works!

3. I couldn't run the tests locally since I'm not NixOS and `pdm` doesn't really work here (I'm using `uv` for all the other projects I'm working on). Hopefully we can just run them in CI.

[danielgafni]

Never mind, figured out you had a non-standard ruff.toml location

[danielgafni]

I'm not sure if it's a good test since both classes are implemented in the same package. Should we split them to separate packages? or what's the best way to test this?

[pawamoy]

Yeah we provide a make format command to format the code, it takes care of using the right config file (located in config/ruff.toml as you noticed).

About NixOS / PDM, not sure why pdm-backend wouldn't work on this OS 🤷 We're using uv too, but building the project with pdm-backend (which is transparently installed as a Python package, in a temp venv, by uv when building, so it should work on any OS really).

Let's decide on the issue whether the preload_modules solution works for you before I review this code 🙂

[danielgafni]

I guess I was too quick with my judgement: indeed pdm works with a uv-provided Python executable (uv installs standalone executables which work on NixOS since they don't rely on shared libraries). So the main uv role here is just to provide a "good" Python executable on NixOS -- the package management part doesn't really matter.

So, as mentioned in #41, preloading dagster breaks things for me. Not sure if there is an easy work-around but this is already good evidence that this feature might be useful anyway (it just has a smaller scope -> no chance to break or affect anything else).

[sneakers-the-rat]

Basically the same as #30 except imports done inline rather than pulling out to separate functions