feat: sync latest ARR implementation

tests/test_booking_current_source_migration.py

@@ -0,0 +1,41 @@
+from pathlib import Path
+import unittest
+
+
+PROJECT_ROOT = Path(__file__).resolve().parents[1]
+UP_PATH = PROJECT_ROOT / "database" / "014_booking_current_source_batch.sql"
+DOWN_PATH = PROJECT_ROOT / "database" / "014_booking_current_source_batch.down.sql"
+
+
+class BookingCurrentSourceMigrationTests(unittest.TestCase):
+    def test_forward_migration_adds_guarded_singleton_and_filters_view(self) -> None:
+        sql = UP_PATH.read_text(encoding="utf-8")
+
+        for required in (
+            "current_database() <> 'booking_test'",
+            "ARR migrations 008 through 013 must be applied first",
+            "CREATE TABLE booking.current_source_batch",
+            "singleton boolean PRIMARY KEY DEFAULT true CHECK (singleton)",
+            "current_source_batch_acceptance_guard",
+            "batch.batch_status = 'accepted'",
+            "FROM booking.current_source_batch AS active_source",
+            "source.source_batch_id = active_source.source_batch_id",
+            "historical batches remain immutable but inactive",
+        ):
+            with self.subTest(required=required):
+                self.assertIn(required, sql)
+
+        self.assertIn("ORDER BY", sql)
+        self.assertIn("LIMIT 1", sql)
+
+    def test_rollback_refuses_after_excel_history_exists(self) -> None:
+        sql = DOWN_PATH.read_text(encoding="utf-8")
+
+        self.assertIn("source_kind = 'booking_excel'", sql)
+        self.assertIn("refusing rollback: Booking Excel source history exists", sql)
+        self.assertIn("multiple accepted Booking source batches exist", sql)
+        self.assertIn("DROP TABLE booking.current_source_batch", sql)
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=2)