added and updated models

specs/models/biz/sale.v

@@ -14,28 +14,30 @@ pub enum SaleStatus {
 
 // Sale represents a sale of products or services
 pub struct Sale {
-	base.Base // Base struct for common fields
+	base.Base // Provides id u32, creation_time, mod_time, comments []u32
 pub mut:
-	id           u32
-	company_id   u32
+	// id u32 is provided by base.Base
+	company_id   u32                // Reference to Company.id that made the sale
 	buyer_name   string
 	buyer_email  string
 	total_amount currency.Currency
 	status       SaleStatus
 	sale_date    ourtime.OurTime
-	created_at   ourtime.OurTime
-	updated_at   ourtime.OurTime
+	// created_at is provided by base.Base.creation_time
+	// updated_at is provided by base.Base.mod_time
 	items        []SaleItem
 }
 
+// SaleItem represents an individual item within a Sale.
+// Its lifecycle is tied to the parent Sale.
 pub struct SaleItem {
 pub mut:
-	id          u32
-	sale_id     u32
-	product_id  u32
-	name        string
+	// id u32 - Removed, component of Sale
+	// sale_id u32 - Removed, implicit link to parent Sale
+	product_id  u32                // Reference to Product.id
+	name        string             // Denormalized product name at time of sale
 	quantity    int
-	unit_price  currency.Currency
+	unit_price  currency.Currency  // Price per unit at time of sale
 	subtotal    currency.Currency
-	active_till ourtime.OurTime // after this product no longer active if e.g. a service
+	service_active_until ourtime.OurTime? // Optional: For services, date until this specific purchased instance is active
 }