Stable multitenancy

PostFundManagement.Domain/Entities/TenantUser.cs

@@ -1,12 +1,13 @@
 namespace PostFundManagement.Domain.Entities;
 
-[EntityTypeConfiguration<TenantUserConfiguration, TenantUser>]
 public class TenantUser : Models.TenantUser
 {
     public virtual Tenant? Tenant { get; set; }
 
+    [ForeignKey(nameof(CreatedBy))]
     public virtual User? Creator { get; set; }
 
+    [ForeignKey(nameof(UserId))]
     public virtual User? User { get; set; }
 }
 
@@ -17,6 +18,8 @@ public sealed class TenantUserConfiguration : IEntityTypeConfiguration<TenantUse
         builder.ToTable(nameof(TenantUser).Pluralize());
 
         builder.HasKey(pk => pk.Id);
+        builder.HasIndex(tu => new { tu.TenantId, tu.UserId }).IsUnique();
+
         builder.Property(f => f.CreatedAt).IsRequired().HasDefaultValueSql("now()");
         builder.Property(f => f.CreatedBy).IsRequired();
         builder.Property(f => f.UserId).IsRequired();