This revision's improvements include: [1] the main plugin entry page has been fully transitioned to Wordpress, [2] the listings page has been fully transitioned to Wordpress, [3] two new methods have been added to the FFI_BE_Essentials class for URL processing, and [4] the FFI_BE_Interception_Manager class loads the content of the page before loading the Wordpress header, so CSS and JS hooks activated by each page can be included in the <head> section of each page, by Wordpress.
This revision has: [1] fully migrated the "book-details" page (formally just the "book" page) to Wordpress, [2] fully migrated the view-listing.php page to Wordpress, [3] fully migrated the search to Wordpress (that was a bean), [4] turned on all error reporting within this plugin during development, [5] added a method to the FFI_BE_Essentials class to fetch the current user's data, and [6] fixed an issue with the FFI_BE_Interception_Manager class giving an error if the requested page was truly not found.