[PR #13930/922b6037 backport][9.0.x] Add CLI options reference documentation

[patchback]

This is a backport of PR #13930 as merged into main (922b603).

Addresses #13973

Summary

Previously, pytest command-line options were only visible via pytest --help, making them difficult to discover and browse online. This PR adds a dedicated CLI options reference page to improve discoverability and provide a better documentation experience.

Changes

Added a new documentation page (doc/en/how-to/cli-options.rst) that organizes commonly used pytest CLI options into logical categories:

• Running and Selecting Tests (-k, -m, -x, --maxfail, --lf, --ff, --sw)
• Output and Verbosity (-v, -q, --tb, -l, -r)
• Reporting and Output Files (--junit-xml, --durations, -s)
• Collection and Test Discovery (--collect-only, --pyargs, --ignore)
• Debugging (--pdb, --trace, --fixtures, --setup-show)
• Configuration (-c, --basetemp, -o)
• Logging (--log-cli-level, --log-level, --log-file)
• Warnings (--disable-warnings, -W)
• Common Option Combinations for typical workflows

Each section includes clear examples, brief explanations, and cross-references to related documentation. The page also links to the complete command-line flag reference for users who need the exhaustive list.

Files Changed

• Added doc/en/how-to/cli-options.rst - new CLI options reference page (307 lines)
• Updated doc/en/how-to/index.rst - added the new page to the table of contents
• Added changelog/4492.doc.rst - changelog entry

Testing

The documentation was successfully built using Sphinx with no errors. All cross-references are valid and the generated HTML renders correctly.