feat: Add flag URL to Country type and update CountryCard component

backend/server/adventures/migrations/0019_collection_updated_at.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.0.7 on 2024-08-05 17:51
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('adventures', '0018_note_links'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='collection',
+            name='updated_at',
+            field=models.DateTimeField(auto_now=True),
+        ),
+    ]