Give every model created/modified timestamps

TimeStampedModel goes on UUIDModel, so all 28 domain models get row birthdays in
one place. Without them the dashboard can only ever describe the present: "42
members" is knowable, "members joined this month" is not, and no metric can show
direction.

Order dropped its own created/modified -- redeclaring a field from an abstract
base is an error, and its column survives as a plain AlterField (verbose_name
only), so no order data moves.

Note for reading early charts: auto_now_add backfills existing rows with a single
migration timestamp, so everything that predates this commit shares one birthday
and will show up as a spike at that instant rather than as real history.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

events/migrations/0009_attendance_created_attendance_modified_event_created_and_more.py

@@ -0,0 +1,69 @@
+# Generated by Django 6.0.6 on 2026-07-13 22:51
+
+import datetime
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('events', '0008_event_created_by'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='attendance',
+            name='created',
+            field=models.DateTimeField(auto_now_add=True, default=datetime.datetime(2026, 7, 13, 22, 51, 35, 565980, tzinfo=datetime.timezone.utc), verbose_name='created'),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='attendance',
+            name='modified',
+            field=models.DateTimeField(auto_now=True, verbose_name='modified'),
+        ),
+        migrations.AddField(
+            model_name='event',
+            name='created',
+            field=models.DateTimeField(auto_now_add=True, default=datetime.datetime(2026, 7, 13, 22, 51, 35, 565998, tzinfo=datetime.timezone.utc), verbose_name='created'),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='event',
+            name='modified',
+            field=models.DateTimeField(auto_now=True, verbose_name='modified'),
+        ),
+        migrations.AddField(
+            model_name='eventseries',
+            name='created',
+            field=models.DateTimeField(auto_now_add=True, default=datetime.datetime(2026, 7, 13, 22, 51, 35, 566017, tzinfo=datetime.timezone.utc), verbose_name='created'),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='eventseries',
+            name='modified',
+            field=models.DateTimeField(auto_now=True, verbose_name='modified'),
+        ),
+        migrations.AddField(
+            model_name='location',
+            name='created',
+            field=models.DateTimeField(auto_now_add=True, default=datetime.datetime(2026, 7, 13, 22, 51, 35, 566033, tzinfo=datetime.timezone.utc), verbose_name='created'),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='location',
+            name='modified',
+            field=models.DateTimeField(auto_now=True, verbose_name='modified'),
+        ),
+        migrations.AddField(
+            model_name='opponent',
+            name='created',
+            field=models.DateTimeField(auto_now_add=True, default=datetime.datetime(2026, 7, 13, 22, 51, 35, 566050, tzinfo=datetime.timezone.utc), verbose_name='created'),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='opponent',
+            name='modified',
+            field=models.DateTimeField(auto_now=True, verbose_name='modified'),
+        ),
+    ]