second review

backend/models.py

@@ -206,7 +206,7 @@ class Invite(Base):
     godfather: Mapped[User] = relationship(
         "User",
         foreign_keys=[godfather_id],
-        lazy="selectin",
+        lazy="joined",
     )
     
     # User who used this invite (null until spent)
@@ -216,7 +216,7 @@ class Invite(Base):
     used_by: Mapped[User | None] = relationship(
         "User",
         foreign_keys=[used_by_id],
-        lazy="selectin",
+        lazy="joined",
     )
     
     # Timestamps