Add index on RewardCampaign for ends_at and starts_at fields; update tests for index verification

twitch/migrations/0020_rewardcampaign_tw_reward_ends_starts_idx.py

@@ -0,0 +1,22 @@
+# Generated by Django 6.0.4 on 2026-04-11 22:41
+
+from django.db import migrations
+from django.db import models
+
+
+class Migration(migrations.Migration):
+    "Add an index on the RewardCampaign model for the ends_at and starts_at fields, to optimize queries that filter by these fields."
+
+    dependencies = [
+        ("twitch", "0019_dropcampaign_campaign_list_indexes"),
+    ]
+
+    operations = [
+        migrations.AddIndex(
+            model_name="rewardcampaign",
+            index=models.Index(
+                fields=["ends_at", "-starts_at"],
+                name="tw_reward_ends_starts_idx",
+            ),
+        ),
+    ]