Document WordPress request types

[szepeviktor]

• https://github.com/szepeviktor/wordpress-website-lifecycle/blob/master/WordPress-internals.md
• https://github.com/felixarntz/felixarntz-mu-plugins/blob/main/felixarntz-mu-plugins/make-site-private.php
• https://github.com/szepeviktor/SentencePress/blob/master/src/Is.php#L88
• favicon.ico
• is_* https://developer.wordpress.org/reference/classes/wp_query/#methods

-> virtual URL or file

[szepeviktor]

Replace Is class szepeviktor/SentencePress#5 (Context/Router)