Added notifications

Added shopping cart and items
Added quotes
Refactored relatinoships
Migrated changes
Refactored cqrs commands and queries
Refactored mappings

LiteCharms.Features/Products/Queries/Handlers/GetProductPriceQueryHandler.cs

@@ -12,6 +12,9 @@ public class GetProductPriceQueryHandler(IDbContextFactory<LeadGeneratorDbContex
 		{
             using var context = await contextFactory.CreateDbContextAsync(cancellationToken);
 
+            if(!await context.Products.AnyAsync(p => p.Id == request.ProductId, cancellationToken))
+                return Result.Fail<ProductPrice>(new Error($"Product {request.ProductId} not found."));
+
             var productPrice = await context.ProductPrices.AsNoTracking()
                 .Where(pp => pp.ProductId == request.ProductId && pp.Active)
                 .OrderByDescending(pp => pp.CreatedAt)