Send notifications about login with new client or country (#4032)

* Send notifications about login with new client or country

* Rebase migration

* Remove immediately

* Fix isort

* Text update

src/pretix/base/migrations/0261_userknownloginsource.py

@@ -0,0 +1,48 @@
+# Generated by Django 4.2.10 on 2024-04-02 15:37
+
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+
+import pretix.helpers.countries
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("pretixbase", "0260_alter_reusablemedium_index_together"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="UserKnownLoginSource",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True, primary_key=True, serialize=False
+                    ),
+                ),
+                ("agent_type", models.CharField(max_length=255, null=True)),
+                ("device_type", models.CharField(max_length=255, null=True)),
+                ("os_type", models.CharField(max_length=255, null=True)),
+                (
+                    "country",
+                    pretix.helpers.countries.FastCountryField(
+                        countries=pretix.helpers.countries.CachedCountries,
+                        max_length=2,
+                        null=True,
+                    ),
+                ),
+                ("last_seen", models.DateTimeField()),
+                (
+                    "user",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="known_login_sources",
+                        to=settings.AUTH_USER_MODEL,
+                    ),
+                ),
+            ],
+        ),
+    ]