add shared pricing resolution with fixed yem price,GRN weighted and FIFO valuation cost fallback

Backend/ERPCore/Program.cs

@@ -90,6 +90,7 @@ builder.Services.AddScoped<IStockService, StockService>();
 builder.Services.AddScoped<IGrnService, GrnService>();
 
 // Sales (Phase 1)
+builder.Services.AddScoped<ISalesPricingService, SalesPricingService>();
 builder.Services.AddScoped<ISalesInvoiceService, SalesInvoiceService>();
 builder.Services.AddScoped<ISalesSlipService, SalesSlipService>();