:sig
DValue* DValue::reference_target()
const DValue* DValue::reference_target() const

:params
return value : resolved target pointer, or 0 when this node is not a usable reference

:see
0_DValue
2_DValue_is_reference
2_DValue_deref

:content
If this node is an internal reference, follows reference links up to the runtime safety limit and returns the final non-reference target. Returns `0` for non-references, null/self references, or chains that still resolve to a reference.

```cpp
if(DValue* target = value.reference_target()) target->set("updated");
```
