feat: Add collapsible curriculum accordion tree, direct video upload to platform, resilient AI asset generation with smart synthesis fallback, and ingest Physics Unit 2

backend/scripts/ingest_physics_unit2.php

@@ -0,0 +1,17 @@
+<?php
+
+require_once __DIR__ . '/../app/bootstrap.php';
+require_once __DIR__ . '/curriculum_markdown_parser.php';
+
+$metadata = [
+    'grade_name'    => 'الصف العاشر الأساسي (Grade 10)',
+    'grade_key'     => 'grade_10',
+    'subject_name'  => 'الفيزياء (Physics 10)',
+    'subject_key'   => 'physics_10',
+    'semester_name' => 'الفصل الدراسي الأول',
+    'semester_key'  => 'semester_1'
+];
+
+$u2 = file_get_contents(__DIR__ . '/unit2_physics_full.md');
+$res = parseAndIngestTextbookMarkdown($u2, $metadata);
+echo "SUCCESS! Ingested Grade 10 Physics Unit 2 (Motion and Forces)!\n";