Add class with custom Ctor AutoMapping by default

[DocSvartz]

Potential issues:

• MaptoTarget cases:

  • Nullable insider case
  • Not Update if using in ctor (can be fix to AutoProperty, custom property only manual mapping)

• Double initialization of member destination (in the constructor and the properties themselves) (not Critical, using in not null branch)

class AutoCtorDestX
{
    public AutoCtorDestX(int x) 
    {
        X = x;
    }

    public int X { get; set; }
}


.Block(Mapster.Tests.AutoCtorDestX $result) {
    .If ($var1 == null) {
        .Return #Label1 { null }
    } .Else {
        .Default(System.Void)
    };
    $result = ($var2 ?? .New Mapster.Tests.AutoCtorDestX($var1.X)); // X is first init , not using if var2 is not null
 
    .Block() {
        $result.X = $var1.X //  X is double init
    };
    .Return #Label1 { $result };
    .Label
        null
    .LabelTarget #Label1:
}

if 

class AutoCtorDestX
{
    public AutoCtorDestX(int x) 
    {
        X = x;
    }

    public int X { get;}  // X is not Update
}