feat: temp barcode templates

models/product.py

@@ -18,6 +18,9 @@ class Product(BaseModel):
     client = relationship('Client', back_populates='products')
     barcodes = relationship('ProductBarcode', back_populates='product', cascade="all, delete-orphan")
 
+    barcode_template_id = Column(Integer, ForeignKey('barcode_templates.id'), nullable=True)
+    barcode_template = relationship('BarcodeTemplate')
+
 
 class ProductBarcode(BaseModel):
     __tablename__ = 'product_barcodes'