[Docs] Update oneshot imports

[UranusSeven]

Purpose

Fix the quant examples. The following import doesn't work anymore.

from llmcompressor.transformers import oneshot

And should be changed to:

from llmcompressor import oneshot

Test Plan

Test the import statement directly.

Test Result

Before this PR:

> python -c "from llmcompressor.transformers import oneshot"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
    from llmcompressor.transformers import oneshot
ImportError: cannot import name 'oneshot' from 'llmcompressor.transformers' (/root/dev/lib/python3.13/site-packages/llmcompressor/transformers/__init__.py). Did you mean: 'Oneshot'?

After this PR:

python -c "from llmcompressor import oneshot"

---

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.
• (Optional) Release notes update. If your change is user facing, please update the release notes draft in the Google Doc.

[mergify]

Documentation preview: https://vllm--28188.org.readthedocs.build/en/28188/

[gemini-code-assist]

Code Review

This pull request correctly updates the import statement for oneshot in several documentation examples. The change from from llmcompressor.transformers import oneshot to from llmcompressor import oneshot aligns with recent library updates, ensuring that the provided code snippets are accurate and runnable for users. The changes are applied consistently across all relevant files, and I find no issues with this update.

[DarkLight1337]

cc @mgoin

[hmellor]

oneshot has been added to the top level init https://github.com/vllm-project/llm-compressor/blob/main/src/llmcompressor/__init__.py

@UranusSeven please fix DCO and we can merge

[UranusSeven]

oneshot has been added to the top level init https://github.com/vllm-project/llm-compressor/blob/main/src/llmcompressor/__init__.py

@UranusSeven please fix DCO and we can merge

Thanks! I've fixed DCO & rebased the PR.