Entity Repo & Controller Refactor (#1690)

* Started mass-refactoring of the current entity repos

* Rewrote book tree logic

- Now does two simple queries instead of one really complex one.
- Extracted logic into its own class.
- Remove model-level akward union field listing.
- Logic now more readable than being large separate query and
compilation functions.

* Extracted and split book sort logic

* Finished up Book controller/repo organisation

* Refactored bookshelves controllers and repo parts

* Fixed issues found via phpunit

* Refactored Chapter controller

* Updated Chapter export controller

* Started Page controller/repo refactor

* Refactored another chunk of PageController

* Completed initial pagecontroller refactor pass

* Fixed tests and continued reduction of old repos

* Removed old page remove and further reduced entity repo

* Removed old entity repo, split out page controller

* Ran phpcbf and split out some page content methods

* Tidied up some EntityProvider elements

* Fixed issued caused by viewservice change

app/Http/Controllers/BookExportController.php

@@ -4,25 +4,16 @@ namespace BookStack\Http\Controllers;
 
 use BookStack\Entities\ExportService;
 use BookStack\Entities\Repos\BookRepo;
-use BookStack\Exceptions\NotFoundException;
 use Throwable;
 
 class BookExportController extends Controller
 {
-    /**
-     * @var BookRepo
-     */
-    protected $bookRepo;
 
-    /**
-     * @var ExportService
-     */
+    protected $bookRepo;
     protected $exportService;
 
     /**
      * BookExportController constructor.
-     * @param BookRepo $bookRepo
-     * @param ExportService $exportService
      */
     public function __construct(BookRepo $bookRepo, ExportService $exportService)
     {
@@ -33,9 +24,6 @@ class BookExportController extends Controller
 
     /**
      * Export a book as a PDF file.
-     * @param string $bookSlug
-     * @return mixed
-     * @throws NotFoundException
      * @throws Throwable
      */
     public function pdf(string $bookSlug)
@@ -47,9 +35,6 @@ class BookExportController extends Controller
 
     /**
      * Export a book as a contained HTML file.
-     * @param string $bookSlug
-     * @return mixed
-     * @throws NotFoundException
      * @throws Throwable
      */
     public function html(string $bookSlug)
@@ -61,9 +46,6 @@ class BookExportController extends Controller
 
     /**
      * Export a book as a plain text file.
-     * @param $bookSlug
-     * @return mixed
-     * @throws NotFoundException
      */
     public function plainText(string $bookSlug)
     {