Create a LSP to interact with pytest fixtures

[entropitor]

What's the problem this feature will solve?

Users can:

• go to the source of a fixture from a test
• get auto-complete for available fixtures (include type annotation) when typing in the arguments of a test function / fixture

And this in all IDEs

Describe the solution you'd like

A custom LSP that could be used in all editors that has the above features (or a subset to begin with). Exposing pytest --fixtures and pytest --fixtures-per-test to the IDEs

Alternative Solutions

Each editor could build manual script for these features using the above 2 commands.

[RonnyPfannschmidt]

this is out of the scope for pytest core - this should be either a plugin or a wrapper

[bluetech]

The proprietary "Pylance" LSP has this feature. Though I assume it is based on static analysis and not actually querying pytest. Static analysis won't be fully accurate but good enough. I hope other LSPs will add it too.