`@deprecated` doesn't work with non-overloaded constructors

Bug Report, To Reproduce, & Actual Behaviour

This is similar to #19588, but that was fixed on master for the case when __init__ is overloaded.

In the non-overloaded case, @deprecated still doesn't report anything (mypy Playground):

To Reproduce

from typing import overload
from typing_extensions import deprecated, Self

class Some:
    @deprecated("reason")
    def __new__(cls, x: str) -> Self: ...

Some('test')  # No reports here

class Some2:
    @deprecated("reason")
    def __init__(self, x: str) -> None: ...

Some2('test')  # No reports here

Expected Behavior

Some('test')  # E: function Some.__new__ is deprecated: reason  [deprecated]
Some2('test')  # E: function Some.__init__ is deprecated: reason  [deprecated]

Your Environment

• Mypy version used: 1.18.2, master

Empieza reproduciendo los casos no sobrecargados de Some.new y Some2.init en el mypy Playground enlazado y, a continuación, compara su tratamiento con el caso sobrecargado de #19588. Se considera terminado cuando ambas llamadas al constructor emitan los diagnósticos [deprecated] esperados que se muestran en el issue.