Add a default blank template to be used (#29)

README.md

@@ -59,6 +59,20 @@ Thoose are completely managed by code and lack of their typical UI.
 
 Accompaniying the core functionality of the mentioned plugins, theese **best practices** are included with this package.
 
+- [x] Allow any post type to use one or more templates, independently from the theme. This is enabled by default for the `page` post type by using
+  ```php
+  add_post_type_support(
+    'page',
+    'post-type-templates',
+    [
+      'templates' => [
+        'blank.php'=>'A blank canvas'
+      ],
+      'path'=>'ABSPATH_TO_TEMPLATE_DIRECTORY'
+    ]
+  );
+  ```
+
 - [x] Allow third-party scripts to be loaded either `defer`ed or `async` via a filter or a URL#hash.
 - [x] Remove jquery 'MIGRATE' console message from frontend.
 - [x] Deliver our figuren.theater favicon as fallback, if non is set

composer.json

@@ -47,6 +47,7 @@
 			"inc/"
 		],
 		"files": [
+			"inc/post-type-templates/namespace.php",
 			"inc/theming/defer-async-loader.php",
 			"inc/theming/favicon-fallback.php",
 			"inc/theming/no-jquery-migrate.php",
@@ -58,9 +59,9 @@
 	"config": {
 		"allow-plugins": {
 			"composer/installers": true,
-			"phpstan/extension-installer": true,
 			"dealerdirect/phpcodesniffer-composer-installer": true,
-			"ergebnis/composer-normalize": true
+			"ergebnis/composer-normalize": true,
+			"phpstan/extension-installer": true
 		}
 	},
 	"extra": {

inc/post-type-templates/namespace.php

@@ -11,7 +11,7 @@
 use function add_action;
 
 const PT_SUPPORT          = 'post-type-templates';
-const TEMPLATES_DIRECTORY = Theming\DIRECTORY . '/templates/post-type-templates/'; 
+const TEMPLATES_DIRECTORY = '/templates/post-type-templates/'; 
 
 /**
  * Bootstrap module, when enabled.
@@ -38,7 +38,7 @@ function load(): void {
 			'templates' => [
 				'blank.php' => \_x( 'Blank', 'Template Title', 'figurentheater' ),
 			],
-			'path'      => TEMPLATES_DIRECTORY,
+			'path'      => Theming\DIRECTORY . TEMPLATES_DIRECTORY,
 		]
 	);
 
@@ -71,7 +71,7 @@ function register_post_type_template( string $post_type ): void {
 		// Try to provide a fallback, if no path was given.
 		// This allows other ft-modules to call add_post_type_support 
 		// with just the name of the template from the ft-theming module, that should be used.
-		$post_type_supports['path'] = TEMPLATES_DIRECTORY;
+		$post_type_supports['path'] = Theming\DIRECTORY . TEMPLATES_DIRECTORY;
 	}
 
 	// Checks for file existence are done inside the Loader class.

templates/post-type-templates/blank.php

@@ -0,0 +1,7 @@
+<?php
+/**
+ * Template Name: Blank
+ * Template Post Type: page
+ *
+ * @package figuren-theater/ft-theming
+ */