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.application/Roles/Contracts.cs

@@ -0,0 +1,24 @@
+namespace Mws.Application.Roles;
+
+public class PermissionEntryDto
+{
+    public string Screen { get; set; } = string.Empty;
+    public bool CanView { get; set; }
+    public bool CanCreate { get; set; }
+    public bool CanEdit { get; set; }
+    public bool CanDelete { get; set; }
+}
+
+public class RoleDto
+{
+    public Guid Id { get; set; }
+    public string Name { get; set; } = string.Empty;
+    public bool IsSystem { get; set; }
+    public List<PermissionEntryDto> Permissions { get; set; } = [];
+}
+
+public class SaveRoleRequest
+{
+    public string Name { get; set; } = string.Empty;
+    public List<PermissionEntryDto> Permissions { get; set; } = [];
+}