Implement support for rolling stock load in consists

ram/consist/migrations/0019_consistitem_load.py

@@ -0,0 +1,18 @@
+# Generated by Django 6.0 on 2026-01-03 12:31
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("consist", "0018_alter_consist_scale"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="consistitem",
+            name="load",
+            field=models.BooleanField(default=False),
+        ),
+    ]