fix: populate questions and options tables, scale AI chapters/checkpoints to video duration, open student lesson discovery

backend/app/Controllers/VideoController.php

@@ -312,10 +312,10 @@ class VideoController
         $lessons = Database::select(
             "SELECT l.id, l.course_id, l.title, l.sequence_order, l.storage_type, l.video_uuid, l.hls_url, l.thumbnail_url, 
                     l.duration_seconds, l.is_free_preview, l.created_at,
-                    c.title as course_title,
+                    COALESCE(c.title, 'توجيهي 2008 — المنهاج المعتمد') as course_title,
                     (SELECT COUNT(*) FROM exams WHERE lesson_id = l.id AND scope = 'in_video_checkpoint') as checkpoints_count
              FROM lessons l
-             JOIN courses c ON l.course_id = c.id
+             LEFT JOIN courses c ON l.course_id = c.id
              {$where}
              ORDER BY l.id DESC"
         );
@@ -354,9 +354,10 @@ class VideoController
 
         $lessonId = (int)$lesson['id'];
 
-        // If lesson has no checkpoints yet, generate them autonomously
+        // If lesson has no checkpoints or missing questions, generate them autonomously
         $existingCount = Database::selectOne("SELECT COUNT(*) as cnt FROM exams WHERE lesson_id = ? AND scope = 'in_video_checkpoint'", [$lessonId]);
-        if (empty($existingCount['cnt'])) {
+        $existingQuestions = Database::selectOne("SELECT COUNT(*) as cnt FROM questions q JOIN exams e ON q.exam_id = e.id WHERE e.lesson_id = ?", [$lessonId]);
+        if (empty($existingCount['cnt']) || empty($existingQuestions['cnt'])) {
             AiVideoAnalyzerService::processLessonAutonomously($lessonId);
             $lesson = Database::selectOne("SELECT * FROM lessons WHERE id = ? LIMIT 1", [$lessonId]);
         }