docs: gunicorn with uvicorn workers

[YorkSu]

Description

• Add a page in the Deployments section for using Uvicorn workers with Gunicorn to deploy ASGI applications.

NOTE

The Gunicorn+Uvicorn pattern is considered legacy for ASGI deployments since Uvicorn 0.30.0+ includes native worker management.

References:

• https://github.com/encode/uvicorn/releases/tag/0.30.0
• New multiprocess manager encode/uvicorn#2183
• FastAPI old docs: https://github.com/fastapi/fastapi/blob/705659bb2277633e75269de9bac9d84cc3c15ae4/docs/en/docs/deployment/server-workers.md
• https://github.com/tiangolo/uvicorn-gunicorn-fastapi-docker/tree/master

Closes

Part of #2609

[provinzkraut]

Don't think we should, as it's not really something I'd recommend anyway, and neither does uvicorn, since they've improved their own proc management.

@litestar-org/members @litestar-org/maintainers if you feel differently, please weigh in

[euri10]

I wouldnt recommend it either, but then we need to update the issue linked so that efforts like this aren't made for nothing.

[provinzkraut]

I wouldnt recommend it either, but then we need to update the issue linked so that efforts like this aren't made for nothing.

Good point. Done.

[YorkSu]

I wouldn't recommend it either.

Considering that users might search for the keyword Gunicorn, would you consider adding a brief description to the manually-with-asgi-server section?

Since some developers might not be aware that the latest Uvicorn versions no longer need to deploy with Gunicorn for multi-workers, providing it could be helpful.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.34%. Comparing base (e5340cf) to head (9488851).

Additional details and impacted files

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  Lines       15756    15756           
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  Misses        124      124           
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[github-actions]

Documentation preview will be available shortly at https://litestar-org.github.io/litestar-docs-preview/3973

[provinzkraut]

I wouldn't recommend it either.

Considering that users might search for the keyword Gunicorn, would you consider adding a brief description to the manually-with-asgi-server section?

Since some developers might not be aware that the latest Uvicorn versions no longer need to deploy with Gunicorn for multi-workers, providing it could be helpful.

I think it should be just that notice