📝Protobuf: updating message types
- int32, uint32, int64, uint64, bool are all compatible (+enum)
- sint32, sint64 are compatible
- string, bytes are compatible (as long as bytes are valid UTF-8)
- embedded messages are compatible with bytes (if bytes contain an encoded version of message)
- fixed32, sfixed32, fixed64, sfixed64 are compatible
- optional and repeated are compatible
- moving one/multiple optional fields into
oneofis safe (as long as only one of the fields is present)