Commit MWS backend source tree

The ASP.NET Core solution (mws.api/mws.application/mws.domain/
mws.infrastructure) existed only as untracked working files. Adding
it to version control, plus a .gitignore for build output and local
tooling directories, so the CQRS/mediator refactor plan has a real
git history to branch and diff against.

mws.infrastructure/Persistence/Configuration/RoleConfiguration.cs

@@ -0,0 +1,16 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+using Mws.Domain.Roles;
+
+namespace Mws.Infrastructure.Persistence.Configuration;
+
+public class RoleConfiguration : IEntityTypeConfiguration<Role>
+{
+    public void Configure(EntityTypeBuilder<Role> e)
+    {
+        e.ToTable("roles");
+        e.HasKey(r => r.Id);
+        e.Property(r => r.Name).HasMaxLength(100).IsRequired();
+        e.HasIndex(r => r.Name).IsUnique();
+    }
+}