feat: add DomainEvent base class and 5 domain event types

domain/marketplace/domain_event.py

@@ -0,0 +1,36 @@
+from dataclasses import dataclass
+from decimal import Decimal
+from uuid import UUID
+
+
+class DomainEvent:
+    pass
+
+
+@dataclass(frozen=True)
+class ClassifiedAdCreated(DomainEvent):
+    id: UUID
+    owner_id: UUID
+
+
+@dataclass(frozen=True)
+class ClassifiedAdTitleChanged(DomainEvent):
+    id: UUID
+    title: str
+
+
+@dataclass(frozen=True)
+class ClassifiedAdTextUpdated(DomainEvent):
+    id: UUID
+    ad_text: str
+
+
+@dataclass(frozen=True)
+class ClassifiedAdPriceUpdated(DomainEvent):
+    id: UUID
+    price: Decimal
+
+
+@dataclass(frozen=True)
+class ClassifiedAdSentForReview(DomainEvent):
+    id: UUID