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

tests/Entity/PageDraftTest.php

@@ -1,11 +1,14 @@
 <?php namespace Tests;
 
-
 use BookStack\Entities\Repos\PageRepo;
 
 class PageDraftTest extends BrowserKitTest
 {
     protected $page;
+
+    /**
+     * @var PageRepo
+     */
     protected $pageRepo;
 
     public function setUp(): void
@@ -85,11 +88,11 @@ class PageDraftTest extends BrowserKitTest
         $newUser = $this->getEditor();
 
         $this->actingAs($newUser)->visit('/')
-            ->visit($book->getUrl() . '/create-page')
-            ->visit($chapter->getUrl() . '/create-page')
+            ->visit($book->getUrl('/create-page'))
+            ->visit($chapter->getUrl('/create-page'))
             ->visit($book->getUrl())
             ->seeInElement('.book-contents', 'New Page');
-        
+
         $this->asAdmin()
             ->visit($book->getUrl())
             ->dontSeeInElement('.book-contents', 'New Page')