Fix: auto-activate participant status on enrollment

Participants stayed in 'registered' status even after being enrolled
in active groups. The collect payment wizard filters by status='active',
making them invisible. Now EnrollmentService transitions registered→active
on enrollment. Also fixed 70 existing participants in oc_sport DB.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Domain/Training/Services/EnrollmentService.php

@@ -95,6 +95,11 @@ public function enroll(Participant $participant, TrainingGroup $group, User $act
             // Update group count
             $this->groupService->incrementCount($group);
 
+            // Activate participant if still in registered status
+            if ($participant->status->value === 'registered') {
+                $participant->update(['status' => 'active']);
+            }
+
             // Auto-create invoice if program has a price (skip if invoice already provided via options)
             if (empty($options['invoice_id']) && (bool) $this->settings->get('auto_invoice_on_enrollment', false)) {
                 $this->createEnrollmentInvoice($enrollment, $participant, $group, $actor);