feat: ? Operator

[afifurrohman-id]

Hi @novalagung this currently is blocking ?

dasarpemrogramanrust/docs/basic/result-type.md

Lines 264 to 266 in facf2ba

	### ◉ Work in progress
	- Operator `?`

This may depend on:

• ? in Testing
• ? in Option
• Trait Object, dyn Keyword
• Smart Pointer

If some of this task is done is good to open PR.

[novalagung]

@afifurrohman-id as of now maintaining this book won't become my first priority so expect some slow response from my end.

there are a bunch of things to be added, I will also review your PR if time allows.