feat: handle unsubscribe

src/domain/subscription.py

@@ -1,4 +1,6 @@
+import datetime
 import uuid
+from enum import StrEnum
 from typing import TYPE_CHECKING
 
 from sqlalchemy import ForeignKey
@@ -11,10 +13,18 @@ if TYPE_CHECKING:
     from .subscriber import Subscriber
 
 
+class SubscriptionStatus(StrEnum):
+    ACTIVE = 'active'
+    UNSUBSCRIBED = 'unsubscribed'
+
+
 class Subscription(domain.Base):
     placement_id: Mapped[uuid.UUID] = mapped_column(ForeignKey('placement.id'), index=True)
     subscriber_id: Mapped[uuid.UUID] = mapped_column(ForeignKey('subscriber.id'), index=True)
+    target_channel_id: Mapped[uuid.UUID] = mapped_column(ForeignKey('target_channel.id'), index=True)
     invite_link: Mapped[str] = mapped_column(index=True)  # По которой пришёл пользователь
+    status: Mapped[SubscriptionStatus] = mapped_column(default=SubscriptionStatus.ACTIVE)
+    unsubscribed_at: Mapped[datetime.datetime | None]
 
     # Relationships
     placement: Mapped['Placement'] = relationship(back_populates='subscriptions')