fix: adjustments based on seb's feedback

- remove eager from shipping_option relationship in `models/custom-shipping-options.ts`
- remove custom_shipping_options relation from cart model

packages/medusa/src/models/cart.ts

@@ -44,8 +44,6 @@
  *       $ref: "#/components/schemas/payment_session"
  *   payment:
  *     $ref: "#/components/schemas/payment"
- *   custom_shipping_options: 
- *     $ref: "#/components/schemas/custom_shipping_option"
  *   shipping_methods:
  *     type: array
  *     items:
@@ -221,13 +219,6 @@ export class Cart {
   @JoinColumn({ name: "payment_id" })
   payment: Payment
 
-  @OneToMany(
-    () => CustomShippingOption,
-    method => method.cart,
-    { cascade: ["insert"] }
-  )
-  custom_shipping_options: CustomShippingOption[]
-
   @OneToMany(
     () => ShippingMethod,
     method => method.cart,

packages/medusa/src/models/custom-shipping-option.ts

@@ -29,7 +29,7 @@ export class CustomShippingOption {
   @Column()
   shipping_option_id: string;
   
-  @ManyToOne(() => ShippingOption, { eager: true })
+  @ManyToOne(() => ShippingOption)
   @JoinColumn({ name: "shipping_option_id" })
   shipping_option: ShippingOption