fix(routing): preserve query string on redirect and prevent crash on root sub-routes

- Router::redirect() now forwards query string parameters from the
  original request to the redirect target. Fixes #303.

- fixUriPath() now checks strlen before accessing $path[0] in the
  while loop, preventing 'Uninitialized string offset 0' when
  grouping sub-routes under root path '/'. Fixes #302.

Author: Ibrahim BinAlshikh

WebFiori/Framework/Router/Router.php

@@ -607,6 +607,10 @@ public static function redirect(string $path, string $to, int $code = 301) {
                 if (!in_array($httpCode, $allowedCodes)) {
                     $httpCode = 301;
                 }
+                $requestedUri = Router::getRouteUri()->getRequestedUri();
+                if ($requestedUri !== null && strlen($requestedUri->getQueryString()) > 0) {
+                    $to .= '?'.$requestedUri->getQueryString();
+                }
                 App::getResponse()->addHeader('location', $to);
                 App::getResponse()->setCode($httpCode);
 
@@ -1104,7 +1108,7 @@ private function fixFilePath($path) {
     private function fixUriPath(string $path): string {
         if (strlen($path) != 0 && $path != '/') {
             if ($path[strlen($path) - 1] == '/' || $path[0] == '/') {
-                while ($path[0] == '/' || $path[strlen($path) - 1] == '/') {
+                while (strlen($path) > 0 && ($path[0] == '/' || $path[strlen($path) - 1] == '/')) {
                     $path = trim($path, '/');
                 }
                 $path = '/'.$path;