docs: Build documentation to check for errors and add xcp.net class docs

[bernhardkaindl]

Pull Request Overview, generated by Copilot PR review

This PR adds documentation building to the development workflow and introduces comprehensive documentation for the xcp.net module. The purpose is to enable documentation validation as part of the build process and provide proper API documentation for networking-related classes.

• Adds documentation building with error checking to the CI pipeline via tox
• Introduces complete API documentation for xcp.net modules using Sphinx
• Updates existing documentation comments to improve formatting and consistency

PS:

• Due to an upstream change in how coverage is calculated, the coverage threshold needed to be reduced.
• This is only a minor reduction by 0.1%, and not caused by any change to the repository itself.
• For GitHub Copilot review: No change to the project itself. No need to comment on this. Minor.

Summary per file

File	Description
xcp/net/ifrename/static.py	Improves formatting of documentation comments with proper list markup and corrects capitalisation
xcp/net/ifrename/logic.py	Converts docstrings to modern Sphinx format with structured parameter and return documentation
tox.ini	Adds docs environment to build documentation with error checking
docs/source/net/*.rst	Creates new RST files for documenting xcp.net modules
docs/source/index.rst	Reorganises documentation structure to include xcp.net module sections
docs/source/conf.py	Removes unused static path configuration
docs/Makefile	Removes @ prefix to show sphinx build output
.pre-commit-config.yaml	Updates pre-commit hook to include documentation building

[bernhardkaindl]

Here is a Preview of the updated docs site from this commit:

Class hierarchies of xcp.accessor and xcp.repository:
If you use dark mode, switch the site to bright mode for an improved view of the class diagrams
by clicking on the half-🌔 icon to switch the docs site do "sun" (day) mode (temporarily):

• https://python-libs-qsfv.onrender.com/accessor.html
• https://python-libs-qsfv.onrender.com/repository.html

xcp.net.* added, Example:

• xcp.net.ifrename.logic
  https://python-libs-qsfv.onrender.com/net/ifrename/ifrename-logic.html

[Copilot]

Pull Request Overview

Copilot reviewed 18 out of 18 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 18 out of 18 changed files in this pull request and generated 2 comments.

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}