docs: add comments

Author: kenjis

system/HTTP/IncomingRequest.php

@@ -451,6 +451,9 @@ public function isSecure(): bool
     public function setPath(string $path, ?App $config = null)
     {
         $this->path = $path;
+
+        // @TODO remove this. The path of the URI object should be a full URI path,
+        //      not a URI path relative to baseURL.
         $this->uri->setPath($path);
 
         $config ??= $this->config;
@@ -481,6 +484,9 @@ public function setPath(string $path, ?App $config = null)
                 $this->uri->setScheme('https');
             }
         } elseif (! is_cli()) {
+            // Do not change exit() to exception; Request is initialized before
+            // setting the exception handler, so if an exception is raised, an
+            // error will be displayed in the production environment.
             // @codeCoverageIgnoreStart
             exit('You have an empty or invalid base URL. The baseURL value must be set in Config\App.php, or through the .env file.');
             // @codeCoverageIgnoreEnd