migrations: Update active status of Channels based on recent activity.

This commit adds a database migration to set is_recently_active=False
for channels based on the last time a message was sent.

The migration follows the same logic used in the
`update_channel_recently_active_status` management command.

This change is particularly useful for self-hosted servers, as it
avoids the need to wait a week for the
`update_channel_recently_active_status` management command to run
via cron.

zerver/migrations/0644_check_update_all_channels_active_status.py

@@ -0,0 +1,55 @@
+# Generated by Django 5.0.9 on 2024-12-23 10:03
+
+from datetime import timedelta
+
+from django.db import migrations, transaction
+from django.db.backends.base.schema import BaseDatabaseSchemaEditor
+from django.db.migrations.state import StateApps
+from django.utils.timezone import now as timezone_now
+
+
+def check_update_all_channels_active_status(
+    apps: StateApps, schema_editor: BaseDatabaseSchemaEditor
+) -> None:
+    Channel = apps.get_model("zerver", "Stream")
+    Message = apps.get_model("zerver", "Message")
+    Realm = apps.get_model("zerver", "Realm")
+    Recipient = apps.get_model("zerver", "Recipient")
+
+    Recipient.STREAM = 2
+    Channel.LAST_ACTIVITY_DAYS_BEFORE_FOR_ACTIVE = 180
+
+    date_days_ago = timezone_now() - timedelta(days=Channel.LAST_ACTIVITY_DAYS_BEFORE_FOR_ACTIVE)
+
+    for realm in Realm.objects.filter(deactivated=False):
+        with transaction.atomic(durable=True):
+            active_channel_ids = (
+                Message.objects.filter(
+                    date_sent__gte=date_days_ago,
+                    recipient__type=Recipient.STREAM,
+                    realm=realm,
+                )
+                .values_list("recipient__type_id", flat=True)
+                .distinct()
+            )
+
+            channels_to_mark_inactive_queryset = Channel.objects.filter(
+                is_recently_active=True, realm=realm
+            ).exclude(id__in=active_channel_ids)
+            channels_to_mark_inactive_queryset.update(is_recently_active=False)
+
+
+class Migration(migrations.Migration):
+    atomic = False
+
+    dependencies = [
+        ("zerver", "0643_realm_scheduled_deletion_date"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            check_update_all_channels_active_status,
+            elidable=True,
+            reverse_code=migrations.RunPython.noop,
+        )
+    ]