Facility booking-mode redesign, multi-plan subscriptions, and Classes

Implements the facility-classes-booking-dashboard plan (backend):

- Facility.BookingMode (single Scheduled/AdHoc choice) replaced with
  independent SupportsClasses/SupportsBooking flags, so one facility
  can run a class and accept walk-in bookings; a running class now
  blocks walk-in booking for its window on both create and reschedule.
- CustomerPlan.GrantsGymAccess + CustomerPlanClass join table let a
  customer hold one gym-access plan plus any number of class-only
  plans. Replaced the old single-subscription resolution
  (GetActiveSubscriptionByCustomerId/HasAnyActiveSubscriptionAsync)
  with gym-access-aware and class-aware resolvers across booking
  creation/cancellation, plan assignment, and customer self-service.
  Fixed ChangeMembershipPlan/renewal plan-changes, which resolved "the
  subscription to replace" by most-recent-created and would have
  deactivated a member's class subscription instead of their gym one.
- New FacilityClass model: recurring class definitions (Daily/Weekly/
  Monthly/Custom) with lazy occurrence generation (8-week horizon,
  race-safe via a unique index) and proper unlimited-capacity handling.
  "Mark not held" replaces the old bare-cancel: cascades to cancel and
  refund every confirmed booking on the occurrence through the same
  core CancelBooking uses, and frees the slot for walk-in booking.
  Scheduling conflicts (a walk-in booking now overlapping a class) are
  surfaced for staff to resolve via the existing Reschedule flow.
- Renamed the pre-existing "AdHoc" booking-mode terminology to
  "WalkIn" throughout (routes, methods, DTOs, the stored BookingMode
  value) for a clearer, simpler name.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Controllers/FacilityController.cs

@@ -33,7 +33,8 @@ namespace Fitness_core_BE.Controllers
             => Response(await _facilityService.CreateFacility(new
             {
                 name = request.Name,
-                bookingMode = request.BookingMode,
+                supportsClasses = request.SupportsClasses,
+                supportsBooking = request.SupportsBooking,
                 description = request.Description,
                 defaultCapacity = request.DefaultCapacity,
                 numberOfUnits = request.NumberOfUnits,
@@ -48,7 +49,8 @@ namespace Fitness_core_BE.Controllers
         {
             var payload = new Dictionary<string, object> { ["facilityId"] = id };
             if (request.Name != null) payload["name"] = request.Name;
-            if (request.BookingMode != null) payload["bookingMode"] = request.BookingMode;
+            if (request.SupportsClasses.HasValue) payload["supportsClasses"] = request.SupportsClasses.Value;
+            if (request.SupportsBooking.HasValue) payload["supportsBooking"] = request.SupportsBooking.Value;
             if (request.Description != null) payload["description"] = request.Description;
             if (request.DefaultCapacity.HasValue) payload["defaultCapacity"] = request.DefaultCapacity.Value;
             if (request.NumberOfUnits.HasValue) payload["numberOfUnits"] = request.NumberOfUnits.Value;
@@ -90,20 +92,21 @@ namespace Fitness_core_BE.Controllers
         [RequiresPermission("bookings")]
         [HttpGet("sessions")]
         public async Task<ActionResult<ApiResponse<object>>> GetSessions(
-            [FromQuery] Guid? facilityId, [FromQuery] DateTime? fromDate, [FromQuery] DateTime? toDate)
+            [FromQuery] Guid? facilityId, [FromQuery] DateTime? fromDate, [FromQuery] DateTime? toDate, [FromQuery] bool includeCancelled = false)
             => Response(await _facilityService.GetSessions(new
             {
                 facilityId,
                 fromDate = fromDate?.ToString("o"),
-                toDate = toDate?.ToString("o")
+                toDate = toDate?.ToString("o"),
+                includeCancelled
             }, HttpContext));
 
         [CustomMiddleware]
         [TenantResolution]
         [RequiresPermission("bookings")]
         [HttpDelete("sessions/{id:guid}")]
-        public async Task<ActionResult<ApiResponse<object>>> CancelFacilitySession(Guid id)
-            => Response(await _facilityService.CancelFacilitySession(new { facilitySessionId = id }, HttpContext));
+        public async Task<ActionResult<ApiResponse<object>>> CancelFacilitySession(Guid id, [FromBody] MarkNotHeldRequest? request)
+            => Response(await _facilityService.CancelFacilitySession(new { facilitySessionId = id, reason = request?.Reason }, HttpContext));
 
         [CustomMiddleware]
         [TenantResolution]