feat(sub): subscription logic (pre release)

db/models/users.py

@@ -6,7 +6,7 @@ from sqlalchemy.orm import Mapped, mapped_column, relationship
 from db.base import Base
 
 if TYPE_CHECKING:
-    from db.models.sessions import Session
+    from db.models import Order, Session, Subscription
 
 
 class User(Base):
@@ -22,6 +22,10 @@ class User(Base):
 
     balance: Mapped[float] = mapped_column(REAL, nullable=False, default=0)
 
+    orders: Mapped[list["Order"]] = relationship("Order", back_populates="user", lazy="selectin")
+    subscription: Mapped["Subscription"] = relationship(
+        "Subscription", back_populates="user", lazy="selectin"
+    )
     sessions: Mapped[list["Session"]] = relationship(back_populates="user", lazy="selectin")
     referal: Mapped["User | None"] = relationship(
         "User",