Inject AppDbContext with parameterized constructor

public class AppDbContext : DbContext, IAppDbContext
{
    private readonly string _connectionString;
    public DbSet<Schedule> Schedules { get; set; } // only expose DbSet for aggregate roots

    public AppDbContext(string connectionString)
    {
        _connectionString = connectionString;
    }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        optionsBuilder.UseSqlServer(_connectionString).UseLazyLoadingProxies();
    }
    
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        modelBuilder.ApplyConfigurationsFromAssembly(Assembly.GetExecutingAssembly());
    }
}

builder.Services.AddScoped<IAppDbContext, AppDbContext>(_ => new AppDbContext(builder.Configuration.GetConnectionString("MsSqlConnection")));