M15: synchronize contracts and acceptance

backend/app/models/revoked_session.py

@@ -0,0 +1,16 @@
+from datetime import datetime
+
+from sqlalchemy import DateTime, String
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.db import Base
+from app.models.mixins import TimestampMixin, UUIDPrimaryKeyMixin
+
+
+class RevokedSession(UUIDPrimaryKeyMixin, TimestampMixin, Base):
+    __tablename__ = "revoked_sessions"
+
+    token_hash: Mapped[str] = mapped_column(String(64), unique=True, index=True, nullable=False)
+    expires_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, index=True
+    )