Emit semantic tokens for user defined conversions

Feature Request

User defined conversions are the only operator overloads that aren't able to be syntax colored to make them more obvious (aside from new and delete, which I reported recently).

I'd like to request semantic tokens to enable syntax highlighting when a user defined conversion is invoked.

The tricky bit is, which token should it be? On the parentheses? Sometimes there aren't any parenthesis.

Perhaps it should be a modifier on the variable being converted? Can we do that if it's an entire expression? Maybe then we could underline the expression without changing the color of the entire thing.

It would also be nice if "go to definition" worked for the conversion, like other operator overloads. But I don't know if that's feasible.

Inizia esaminando come l’estensione emette attualmente i semantic tokens e supporta go-to-definition per gli altri overload degli operatori C++. Confronta gli esempi di conversione segnalati, inclusi i casi senza parentesi, e determina una rappresentazione del token che possa essere applicata in modo coerente. Il lavoro è completo quando il comportamento, la scelta del token ed eventuale supporto per la navigazione alla definizione sono specificati e coperti per le forme di conversione pertinenti.