In reality you should be able to get an anonymized reference number to show your vote was tabulated correctly though.

The reason there is no such thing in elections, is to prevent vote buying/extortion.

In Italy it's such an extreme problem that any ballot where the party is not marked with a cross on the party logo and (if present) a block capital name next to it on the provided line, is automatically discounted, because stuff like writing a name a specific way or using crosses, checks, dots, or other symbols was used to track vote buying/voter intimidation in mafia controlled territories.

Some vote counters and polling station overseers would be on the take and keep track of if the votes they expected to see showed up when counting ballots and report back.

If you were able in any way to prove something beyond the equivalent of an "I voted" sticker it would immediately be used to ensure people voted a certain way or to exact some sort of backlash on those who didn't.