Custom `Option` type with default value?

[Balazs Szabo]

Hi,

Proto2 and 2023 Editions have default value support. Would it be possible to use a custom `Option` type, that has a default value and returns it on `.get` (instead of throwing an error)?

It would be also useful for proto 3 where the default value is 0 and an empty string.

It would work the same way for message types as well (`.get` would return the default instance).

It would give us the opportunity to avoid checking the existence of optional fields or use `.getOrDefault` all the time.

WDYT?

Balázs