Update file permissions and enhance error handling in API responses

public/html_loader.php

@@ -93,6 +93,10 @@ class HTMLLoader {
         if ($showAppName) {
             $call = new APICall("settings/appname.php");
             $response = $call->response;
+            if (isset($response["error"])) {
+                $this->showError("Failed to get Application Name: API Returned an error: " . $response["error_text"]);
+            }
+
             $app_name = $response["data"]["application_name"];
 
             $html = str_replace("%appname%", $app_name, $html);