order thinks on the front page by time of last edit

instead of time of creation

thinks/migrations/0005_think_last_edited.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.0.3 on 2025-04-26 07:50
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('thinks', '0004_think_creation_time'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='think',
+            name='last_edited',
+            field=models.DateTimeField(blank=True, null=True),
+        ),
+    ]