Cannot give same name to getter and setter

```rust
/// JS Setter
/// Js: obj.flag = 10;
#[node_bindgen(setter, name = "flag")]
fn set_flag(&mut self, val: bool) {
self.flag = val;
}

/// JS getter
/// Js: let y = obj.flag;
#[node_bindgen(getter, name = "flag")]
fn get_flag(&self) -> bool {
self.flag
}
```
Same name failed to assign both setter and getter. It change getter name to "flag1", it works fine.

Start by reproducing the Rust attribute-macro case shown, using the same getter and setter name. Trace how getter and setter names are handled, then add a regression test confirming both bindings work with the shared name.

Written by the indexing model from the issue text.