Make the async processing service (psv2) the default and update all existing projects

ami/main/migrations/0094_enable_async_pipeline_workers.py

@@ -0,0 +1,47 @@
+"""
+Turn on the ``async_pipeline_workers`` feature flag for every existing project.
+
+This rolls out async ML processing (workers that pull tasks from the NATS queue
+instead of the synchronous push API) to all projects at once. New projects keep
+the model default of ``False`` until they are opted in separately; this migration
+only updates rows that exist at deploy time.
+
+The flag lives inside the ``feature_flags`` JSONB column (a ``ProjectFeatureFlags``
+pydantic model). We read each project's flags through the historical model, set the
+one boolean, and write it back. The reverse flips the flag back off for every
+project — a blanket disable. It does not restore per-project values from before the
+rollout, because the field default is ``False`` and this is the first global enable,
+so no project is expected to have been ``True`` beforehand.
+"""
+
+from django.db import migrations
+
+
+def enable_async_pipeline_workers(apps, schema_editor):
+    Project = apps.get_model("main", "Project")
+    for project in Project.objects.all():
+        flags = project.feature_flags
+        if not flags.async_pipeline_workers:
+            flags.async_pipeline_workers = True
+            project.feature_flags = flags
+            project.save(update_fields=["feature_flags"])
+
+
+def disable_async_pipeline_workers(apps, schema_editor):
+    Project = apps.get_model("main", "Project")
+    for project in Project.objects.all():
+        flags = project.feature_flags
+        if flags.async_pipeline_workers:
+            flags.async_pipeline_workers = False
+            project.feature_flags = flags
+            project.save(update_fields=["feature_flags"])
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("main", "0093_occurrence_project_score_index"),
+    ]
+
+    operations = [
+        migrations.RunPython(enable_async_pipeline_workers, disable_async_pipeline_workers),
+    ]