feat: Optimize image hash checks with bulk queries and add database indexing for performance

longs/migrations/0035_alter_longseriesimage_image_blake3_hash.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.2.7 on 2026-05-11 11:06
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('longs', '0034_exam_created_exam_updated'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='longseriesimage',
+            name='image_blake3_hash',
+            field=models.CharField(blank=True, db_index=True, max_length=64, null=True),
+        ),
+    ]