overload with wrong return type is ignored

Bug Report

When one of the alternatives of an overload has a return type T which is a subtype of the return type of the annotation U but that the body of the function returns a type V which is a subtype of U but not T, no error is reported

To Reproduce

from typing import overload

@overload
def f(a: int) -> str:
    ...

# this is completely wrong
@overload
def f(a: str) -> bool:
    ...


def f(a: str | int) -> str | bool:
    return "Hello"

reveal_type(f("some string"))

https://mypy-play.net/?mypy=latest&python=3.12&flags=strict&gist=83c5a353e087d8bbe03d542e7340b4b5

Expected Behavior

mypy should complain that the body of the function returns an str which is incompatible with type bool (overload 2)

More generally, for each overload signature, mypy should check that the body of the function typechecks with the overload signature.

Actual Behavior

mypy reports no error

main.py:16: note: Revealed type is "builtins.bool"
Success: no issues found in 1 source file

Inizia con il riproduttore Python mostrato in main.py ed eseguilo con la configurazione strict di mypy-play collegata. Traccia come le firme di overload vengono verificate rispetto al tipo restituito dell’implementazione. Il lavoro è completato quando mypy segnala il ritorno str incompatibile per overload 2 e la regressione è coperta da un test.