Update article with DB mapping and migration images

Added a section on configuring the database mapping in the base DbContext class and included instructions for adding EF Core migrations using ABP Studio. Added three illustrative screenshots to support the migration steps.

docs/en/Community-Articles/2025-07-26-Separate-Tenant-Schema/POST.md

@@ -237,6 +237,37 @@ namespace MtDemoApp
 }
 ````
 
+### Configuring the Database Mapping
+
+Open the `MtDemoAppDbContextBase` class and add the following configuration inside the `OnModelCreating` method:
+
+````csharp
+builder.Entity<Product>(b =>
+{
+    b.ToTable("Products");
+    b.ConfigureByConvention(); //auto-configure for the base class properties
+    b.Property(x => x.Name).IsRequired().HasMaxLength(100);
+});
+````
+
+We made the configuration in the base class since the `Products` table should be created in all databases, not only in the main database.
+
 ### Add a New Database Migration
 
+To add a new EF Core database migration, we can use ABP Studio UI, or EF Core command-line commands. I will show both of these approaches here.
+
+#### Use ABP Studio to Add Database Migrations
+
+...
+
+![abp-studio-add-migration](abp-studio-add-migration.png)
+
+...
+
+![abp-studio-add-migration-set-name](abp-studio-add-migration-set-name.png)
+
+...
+
+![abp-studio-add-migration-select-dbcontext](abp-studio-add-migration-select-dbcontext.png)
+
 TODO