[JohnVillalovos]

Fix the level 4 findings in WebServices/ and remove it from the phpstan_next exclude list:

• Mark ReservationRequest's recurrenceRule, startReminder, endReminder and retryParameters, and ResourceRequest's statusId, as nullable. They come from client JSON and may be omitted, so the existing empty()/isset() guards are correct.
• Mark ScheduleWebServiceView::$startDate as nullable; the slots endpoint now passes null when startDateTime is omitted.
• Drop write-only properties from ReservationRequestResponseFacade (retry and waitlist state) and ScheduleWebServiceView (availability and concurrency flags). Their setters remain because the page interfaces require them; the API does not report these values.
• Remove the unused ReservationsWebService::FilterProvided().

Assisted-by: Claude:claude-opus-5-5

[Copilot]

🟢 Approval recommended

No active review issues remain, and the changes align nullable inputs and remove unused code to support the intended PHPStan level 4 coverage.

No open issues 🎉

What changed in this PR

This pull request enables PHPStan level 4 analysis for WebServices/ by aligning nullable types with client input, removing unused state and helpers, and updating the exclusion list.

Changes:

• Mark optional request and schedule fields as nullable.
• Remove unused retry, waitlist, availability, and concurrency properties while preserving required interface setters.
• Remove the unused FilterProvided() helper.
• Remove WebServices/ from the PHPStan level 4 exclusion list.

File	Description
WebServices/​SchedulesWebService.php	Makes the schedule start date nullable and removes unused availability/concurrency state.
WebServices/​ReservationsWebService.php	Removes the unused FilterProvided() helper.
WebServices/​Requests/​Resource/​ResourceRequest.php	Marks optional statusId input as nullable.
WebServices/​Requests/​ReservationRequest.php	Marks optional recurrence, reminder, and retry fields as nullable.
WebServices/​Controllers/​ReservationSaveController.php	Removes unused retry and waitlist response properties while preserving required interface setters.
phpstan_next.neon	Removes WebServices/ from the PHPStan level 4 exclusion list.

_{Review effort: Lite}