[ty] Fix handling of metaclasses in `object.<CURSOR>` completions
Basically, we weren't quite using `Type::member` in every case
correctly. Specifically, this example from @sharkdp:
```
class Meta(type):
@property
def meta_attr(self) -> int:
return 0
class C(metaclass=Meta): ...
C.<CURSOR>
```
While we would return `C.meta_attr` here, we were claiming its type was
`property`. But its type should be `int`.
Ref https://github.com/astral-sh/ruff/pull/19216#discussion_r2197065241
