Adding attribute examples to doc

[natsuki-engr]

Many of examples in doc are written using only annotation.
As mentioned in #1555 , I prefer to using attributes and I'd like to add more examples using attributes for developers who are less familiar with attribute syntax (including myself).

I've tried adding to faq.md. (#1699 )
I'll continue adding attribute syntax examples to other pages as well - what do you think about this approach?