Update PHP language server docs (#44001)

Reformat document structure like other language docs, improve
information flow, add missing requirements, and fix typos.

Release Notes:

- N/A

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Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>
74a1b5d14dLiffindra Angga Zaaldian committed on 12/4/2025, 6:04:06 PM· committed by GitHubparent07af011
1 file changedLine totals unavailable