php.php: install-version, remove-version, version-extensions, install-extension,
remove-extension, fpm-action endpoints. versions now returns fpm_active status
and panel_php (current runtime version).
admin.js phpManager(): grid of installed/not-installed versions with Install/
Remove/Restart FPM buttons; Extensions panel slides in below with filterable
list, dropdown of common extensions + custom input, per-extension Remove buttons.
Panel PHP info card shows which version NovaCPX runs on.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>