Implement verified curriculum, video review, watch sessions, ledger safeguards, and remove demo data

backend/scripts/video_upload_worker.php

@@ -19,6 +19,16 @@ function updateVideoTask(string $file, array $changes): void {
 if ($taskId === '' || !file_exists($stateFile)) exit(1);
 $task = json_decode(file_get_contents($stateFile), true) ?: [];
 
+// Legacy worker has no teacher_submission/video_version binding and therefore
+// cannot prove which curriculum lesson or candidate it is publishing. Keep the
+// uploaded file for an operator; do not create or overwrite a lesson by title.
+updateVideoTask($stateFile, [
+    'status' => 'needs_submission_pipeline',
+    'progress' => 0,
+    'message' => 'هذا العامل موقوف حتى يمرر مسار الإرسال نسخة فيديو مرتبطة بالدرس المنهجي.',
+]);
+exit(2);
+
 try {
     updateVideoTask($stateFile, ['status' => 'processing', 'progress' => 15, 'message' => 'جاري تحويل الفيديو إلى HLS...']);
     $file = (string)($task['file'] ?? '');