mypy doesn't escape typevars from generics in self-type

Bug Report

Passing a callable to another which matches the typevar with another typevar doesn't allow passing them into the return type. (if that makes no sense, the reproducer below is simple)

To Reproduce

from typing import Generic, TypeVar, Callable

T = TypeVar("T")
V = TypeVar("V")

class X(Generic[T]):
    def f(self: X[Callable[[V], None]]) -> Callable[[V], V]:
        def inner_f(v: V) -> V:
            return v

        return inner_f

reveal_type(X[Callable[[T], None]]().f())  # N: Revealed type is "def (Never) -> Never"
# ^ this should keep the generic

Expected Behavior

I don't expect a Never.

Your Environment

Checked on mypy playground.

• Mypy version used: v1.14
• Mypy command-line flags: --strict
• Mypy configuration options from mypy.ini (and other config files): N/A
• Python version used: 3.12

Inizia eseguendo il riproduttore generico del self-type fornito con mypy v1.14 e --strict, quindi esamina come reveal_type risolve XCallable[[T], None].f(). Traccia il percorso di inferenza dei tipi responsabile del risultato e considera completata la issue quando la Callable restituita conserva il suo tipo generico invece di diventare (Never) -> Never.