Add instructor group-class roster view under My Lessons

Instructors can now see their own group classes under My Lessons →
My Group Classes (view_own_lessons): each class shows its active
enrolment count against capacity plus a roster of enrolled students
with enrolment and payment status.

GroupClassController gains renderInstructorPage(), backed by the
existing per-instructor enrolment query and a newly injected
PaymentRepository for payment status. Wired as a submenu under the
existing My Lessons menu, inside the same !view_all_lessons guard so
owner-operators don't get a duplicate item.

Closes #71

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/GroupClass/GroupClassController.php

@@ -4,13 +4,16 @@ declare(strict_types=1);
 namespace Unsupervised\Schedular\GroupClass;
 
 use Unsupervised\Schedular\Auth\RoleManager;
+use Unsupervised\Schedular\Offering\Offering;
 use Unsupervised\Schedular\Offering\OfferingRepository;
+use Unsupervised\Schedular\Payment\PaymentRepository;
 
 class GroupClassController {
 
 	public function __construct(
 		private EnrollmentRepository $enrollments,
 		private OfferingRepository $offerings,
+		private PaymentRepository $payments,
 	) {}
 
 	public function renderPage(): void {
@@ -34,4 +37,54 @@ class GroupClassController {
 
 		include USC_PLUGIN_DIR . 'templates/admin/group-classes.php';
 	}
+
+	/**
+	 * Instructor view: their own group classes with per-class rosters. Each class
+	 * shows its enrolment count against capacity plus a roster of enrolled
+	 * students with enrolment and payment status.
+	 */
+	public function renderInstructorPage(): void {
+		if ( ! current_user_can( RoleManager::CAP_VIEW_LESSONS ) ) {
+			wp_die( esc_html__( 'You do not have permission to view group classes.', 'unsupervised-schedular' ) );
+		}
+
+		$instructorId = get_current_user_id();
+		$enrollments  = $this->enrollments->findByInstructor( $instructorId );
+
+		$classes = array_map(
+			function ( Offering $offering ) use ( $enrollments ): array {
+				$roster   = [];
+				$enrolled = 0;
+
+				foreach ( $enrollments as $enrollment ) {
+					if ( $enrollment->offeringId !== $offering->id ) {
+						continue;
+					}
+
+					if ( Enrollment::STATUS_ACTIVE === $enrollment->status ) {
+						++$enrolled;
+					}
+
+					$student = get_userdata( $enrollment->studentId );
+					$payment = null !== $enrollment->paymentId ? $this->payments->findById( $enrollment->paymentId ) : null;
+
+					$roster[] = [
+						'student' => $student ? $student->display_name : (string) $enrollment->studentId,
+						'status'  => $enrollment->status,
+						'payment' => $payment?->status,
+					];
+				}
+
+				return [
+					'title'    => $offering->title,
+					'capacity' => $offering->capacity,
+					'enrolled' => $enrolled,
+					'roster'   => $roster,
+				];
+			},
+			$this->offerings->findAll( $instructorId, Offering::KIND_GROUP_CLASS )
+		);
+
+		include USC_PLUGIN_DIR . 'templates/admin/my-group-classes.php';
+	}
 }