Make pocketmine\PATH and pocketmine\RESOURCE_PATH always available

these are non-dependent on environment, so they can be determined with no external input.
    This fixes 2 PHPStan issues, fixes some code that couldn't run outside of PM, and makes it easier to write code that depends on PM.

composer.json

@@ -38,6 +38,7 @@
          "": ["src"]
       },
       "files": [
+         "src/pocketmine/CoreConstants.php",
          "src/pocketmine/GlobalConstants.php",
          "src/pocketmine/VersionInfo.php"
       ]

phpstan.neon.dist

@@ -87,11 +87,6 @@ parameters:
 			count: 1
 			path: src/pocketmine/level/generator/normal/Normal.php
 
-		-
-			message: "#^Used constant pocketmine\\\\RESOURCE_PATH not found\\.$#"
-			count: 1
-			path: src/pocketmine/network/mcpe/protocol/StartGamePacket.php
-
 		-
 			message: "#^Constructor of class pocketmine\\\\scheduler\\\\TaskScheduler has an unused parameter \\$logger\\.$#"
 			count: 1
@@ -109,18 +104,10 @@ parameters:
 			message: "#^Constant pocketmine\\\\GIT_COMMIT not found\\.$#"
 			path: src
 
-		-
-			message: "#^Constant pocketmine\\\\PATH not found\\.$#"
-			path: src
-
 		-
 			message: "#^Constant pocketmine\\\\PLUGIN_PATH not found\\.$#"
 			path: src
 
-		-
-			message: "#^Constant pocketmine\\\\RESOURCE_PATH not found\\.$#"
-			path: src
-
 		-
 			message: "#^Constant pocketmine\\\\START_TIME not found\\.$#"
 			path: src

src/pocketmine/CoreConstants.php

@@ -0,0 +1,33 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine;
+
+// composer autoload doesn't use require_once and also pthreads can inherit things
+if(defined('pocketmine\_CORE_CONSTANTS_INCLUDED')){
+	return;
+}
+define('pocketmine\_CORE_CONSTANTS_INCLUDED', true);
+
+define('pocketmine\PATH', dirname(__DIR__, 2) . '/');
+define('pocketmine\RESOURCE_PATH', __DIR__ . '/resources/');

src/pocketmine/PocketMine.php

@@ -171,17 +171,11 @@ namespace pocketmine {
 		error_reporting(-1);
 		set_ini_entries();
 
-		if(\Phar::running(true) !== ""){
-			define('pocketmine\PATH', \Phar::running(true) . "/");
-		}else{
-			define('pocketmine\PATH', dirname(__FILE__, 3) . DIRECTORY_SEPARATOR);
-		}
-
 		$opts = getopt("", ["bootstrap:"]);
 		if(isset($opts["bootstrap"])){
 			$bootstrap = realpath($opts["bootstrap"]) ?: $opts["bootstrap"];
 		}else{
-			$bootstrap = \pocketmine\PATH . 'vendor/autoload.php';
+			$bootstrap = dirname(__FILE__, 3) . '/vendor/autoload.php';
 		}
 		define('pocketmine\COMPOSER_AUTOLOADER_PATH', $bootstrap);
 
@@ -212,8 +206,6 @@ namespace pocketmine {
 
 		define('pocketmine\GIT_COMMIT', $gitHash);
 
-		define('pocketmine\RESOURCE_PATH', \pocketmine\PATH . 'src' . DIRECTORY_SEPARATOR . 'pocketmine' . DIRECTORY_SEPARATOR . 'resources' . DIRECTORY_SEPARATOR);
-
 		$opts = getopt("", ["data:", "plugins:", "no-wizard", "enable-ansi", "disable-ansi"]);
 
 		define('pocketmine\DATA', isset($opts["data"]) ? $opts["data"] . DIRECTORY_SEPARATOR : realpath(getcwd()) . DIRECTORY_SEPARATOR);