major refactoring adding vendor and customer features

models/database/marketplace_product.py

@@ -21,7 +21,7 @@ class MarketplaceProduct(Base, TimestampMixin):
     availability = Column(String, index=True)  # Index for filtering
     price = Column(String)
     brand = Column(String, index=True)  # Index for filtering
-    gtin = Column(String, index=True)  # Index for stock lookups
+    gtin = Column(String, index=True)  # Index for inventory lookups
     mpn = Column(String)
     condition = Column(String)
     adult = Column(String)
@@ -57,13 +57,6 @@ class MarketplaceProduct(Base, TimestampMixin):
     )  # Index for marketplace filtering
     vendor_name = Column(String, index=True, nullable=True)  # Index for vendor filtering
 
-    # Relationship to stock (one-to-many via GTIN)
-    stock_entries = relationship(
-        "Stock",
-        foreign_keys="Stock.gtin",
-        primaryjoin="MarketplaceProduct.gtin == Stock.gtin",
-        viewonly=True,
-    )
     product = relationship("Product", back_populates="marketplace_product")
 
     # Additional indexes for marketplace queries