core/types: A try to create panic-safe Golang types and some experiments with the language type system

A try to create panic-safe Golang types and some experiments with the language type system

surdeus fa3fdf8002 feat: better nilable types.		7 달 전
cmd	fa3fdf8002 feat: better nilable types.	7 달 전
objects	b9e40a0963 Init.	9 달 전
.gitignore	fa3fdf8002 feat: better nilable types.	7 달 전
go.mod	b9e40a0963 Init.	9 달 전
id.go	fa3fdf8002 feat: better nilable types.	7 달 전
interface.go	b9e40a0963 Init.	9 달 전
main.go	b9e40a0963 Init.	9 달 전
mut.go	b9e40a0963 Init.	9 달 전
nil.go	fa3fdf8002 feat: better nilable types.	7 달 전
ptr.go	b9e40a0963 Init.	9 달 전
valid.go	fa3fdf8002 feat: better nilable types.	7 달 전