docs: autogenerate app config docs

[psychedelicious]

What type of PR is this? (check all applicable)

• Refactor
• Feature
• Bug Fix
• Optimization
• Documentation Update
• Community Node Submission

Have you updated all relevant documentation?

• Yes
• No

Description

While iterating on MM2 configs, I wanted to update the docs. This proved very tedious and I discovered the configuration docs were terribly out of date.

This prompted me to automate updating the app config docs. The meat-n-potatoes are these changes:

docs: autogenerated app config docs

mkdocs can autogenerate python class docs from its docstrings. Our config is a pydantic model.

It's tedious and error-prone to duplicate docstrings from the pydantic field descriptions to the class docstrings.

• Add helper function to generate a mkdocs-compatible docstring from the InvokeAIAppConfig class fields

scripts: add script to update config docstring

• Add script to call config docstring helper function and write the docstring to the file directly
• Add make target for this script

The docstrings for InvokeAIAppConfig now have a test that confirms they are current. If the test fails, you can run make update-config-docstring to update the docstrings.

The CONFIGURATION.md doc is updated to autogenerate docs for InvokeAIAppConfig. Much of the individual setting documentation is removed, but a few bits that give extra useful context are retained.

QA Instructions, Screenshots, Recordings

Run mkdocs serve and go to Features -> Configuration to see the docs.

Merge Plan

This PR can be merged when approved