feature: support of pydantic-settings

[john-pixforce]

It would be highly beneficial to add support for pydantic-settings within griffe-pydantic. Currently, griffe-pydantic effectively handles Pydantic BaseModel classes, but lacks the ability to process pydantic_settings.BaseSettings classes.

https://docs.pydantic.dev/latest/concepts/pydantic_settings/

Motivation:

pydantic-settings is widely used for managing application configurations, particularly in modern Python projects. Integrating it with griffe-pydantic would:

• Simplify Configuration Documentation: Enable automatic generation of documentation for settings models, including environment variable names, default values, and validation constraints.
• Enhance Developer Experience: Provide a consistent and streamlined approach to documenting both data models and configuration settings within Pydantic-based projects.
• Improve Code Maintainability: Ensure that configuration settings are documented alongside the rest of the codebase, reducing the risk of inconsistencies.

[sneakers-the-rat]

Same with SQLModel classes. I can't tell why the plugin doesn't already handle them actually, if maintainer points me towards a fix i'd write it :).

From what i can tell the only filtering happens here:

griffe-pydantic/src/griffe_pydantic/_internal/extension.py

Lines 55 to 56 in 187b4b8

	if issubclass(node.obj, pydantic.BaseModel):
	self._recorded.append((node, cls))

but both SQLModel and BaseSettings models are subclasses of BaseModel.

[pawamoy]

It's probably that the static analysis agent only checks for pydantic.BaseModel in the base classes, non-recursively. It doesn't try to load additional packages like SQLModel so it wouldn't know that sqlmodel.SQLModel (or whatever the path is) actually inherits from pydantic.BaseModel too.

[sneakers-the-rat]

Aha, if it's just static, then might be as simple as accepting config to look for a different base class name? Wouldn't handle any specific customizations one might want for pydantic-settings, so not to hijack the issue, but I'll try my hand at it this evening.