docs: Document auth-logout input of setup-pixi v0.11.0

[pavelzw]

Description

Documents the new auth-logout input of setup-pixi, which replaces the removed persist-credentials input (breaking change in setup-pixi@v0.11.0), and bumps the setup-pixi version in the GitHub Actions docs to v0.11.0.

auth-logout controls when pixi auth logout <auth-host> runs: post (default, in the post step at the end of the job), after-install (previously persist-credentials: false) or never (previously persist-credentials: true).

Depends on prefix-dev/setup-pixi#291, should be merged after setup-pixi@v0.11.0 is released.

How Has This Been Tested?

Docs only. The section mirrors the README of prefix-dev/setup-pixi#291.

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  • I have tested any AI-generated content in my PR.
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Tools: Claude Code

Checklist:

• I have made corresponding changes to the documentation