added option to expand sub-storage stocks to display all components from sub_storages

this comes in handy for assortment boxes using sub storages for each individual compartment which usually only holds a single stock

shimatta_kenkyusho/parts/migrations/0013_storage_expand_sub_storage_stocks.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.1.3 on 2025-01-25 13:20
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('parts', '0012_storage_verbose_name'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='storage',
+            name='expand_sub_storage_stocks',
+            field=models.BooleanField(default=False),
+        ),
+    ]