refactor: move `@doc_status` into compiler

[takahashim]

#1698 と同じような課題ですが、@doc_statusやcheck_nested_minicolumnなどがbuilderのあちこちに分散しているのを避けるべく、compiler側に移動してみました。

[kmuto]

Sorry for bothering, I've already rewritten raw atmark Compiler to quoted string @Compiler in review message of this thread. But during you post a message here, it means you subscribe this thread. I'll remove your posts manually.