Break out new Externalities graph type into three separate graph types

Each of these scenarios has various modes within it, so I think these
should be separate graph types actually.

econplayground/main/migrations/0125_alter_graph_graph_type.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.1.6 on 2025-02-27 20:55
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0124_alter_graph_graph_type'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='graph',
+            name='graph_type',
+            field=models.PositiveSmallIntegerField(choices=[(0, 'Linear Demand and Supply'), (1, 'Input Markets'), (3, 'Cobb-Douglas Production Graph'), (5, 'Consumption-Leisure: Constraint'), (7, 'Consumption-Saving: Constraint'), (8, 'Linear Demand and Supply: 3 Functions'), (9, 'Linear Demand and Supply: Areas'), (10, 'Input Markets: Areas'), (11, 'Consumption-Saving: Optimal Choice'), (15, 'Consumption-Leisure: Optimal Choice'), (12, 'Input-Output Illustrations'), (13, 'Linear Demand and Supply: 2 Diagrams'), (14, 'Input Markets: 2 Diagrams'), (16, 'Template Graph'), (17, 'Optimal Choice: Consumption with 2 Goods'), (18, 'Cost Functions'), (20, 'Price Elasticity of Demand and Revenue'), (21, 'Optimal Choice: Cost-Minimizing Production Inputs'), (22, 'Tax Rate and Revenue'), (23, 'Taxation in Linear Demand and Supply'), (24, 'Tax Supply and Demand vs. Tax Revenue'), (25, 'Linear Demand and Supply - Surplus Policies'), (26, 'Negative Production Externality - Producer'), (27, 'Negative Production Externality - Industry'), (28, 'Positive Externality - Industry')], default=0),
+        ),
+    ]

econplayground/main/models.py

@@ -42,7 +42,11 @@
     (24, 'Tax Supply and Demand vs. Tax Revenue'),
 
     (25, 'Linear Demand and Supply - Surplus Policies'),
-    (26, 'Externalities'),
+
+    # Externalities
+    (26, 'Negative Production Externality - Producer'),
+    (27, 'Negative Production Externality - Industry'),
+    (28, 'Positive Externality - Industry'),
 )
 
 ASSIGNMENT_TYPES = (

media/js/src/utils.js

@@ -415,7 +415,13 @@ const displayGraphType = function(gType) {
             name = 'Linear Demand and Supply - Surplus Policies';
             break;
         case 26:
-            name = 'Externalities';
+            name = 'Negative Production Externality - Producer';
+            break;
+        case 27:
+            name = 'Negative Production Externality - Industry';
+            break;
+        case 28:
+            name = 'Positive Production Externality - Industry';
             break;
         default:
             break;