✨ Add Raw RRULE field; clarify FREQ/COUNT; PHP 8 service update

• ➕ Add to Views row plugin
• 👁️ Hide COUNT field unless FREQ selected (#states)
• 🏷️ Relabel frequency/count fields; clearer help
• ♻️ Prefer raw RRULE in service, fallback to FREQ+COUNT; minimal adapter helper
• 🧹 PHP 8/Drupal CS tidy

Closes #3540328