refactor: towards PHP 8.4 and PHP 8.5

Signed-off-by: otengkwame <developerkwame@gmail.com>

Author: otengkwame

CodeIgniter/Framework/core/CI.php

@@ -133,14 +133,8 @@ protected function basepath()
      */
     protected function charset()
     {
-        ini_set('default_charset', $charset = strtoupper(config_item('charset')));
-
+        $charset = strtoupper(config_item('charset')); // Define $charset
         defined('MB_ENABLED') || define('MB_ENABLED', extension_loaded('mbstring'));
-
-        $encoding = 'mbstring.internal_encoding';
-
-        ! ini_get($encoding) && ini_set($encoding, $charset);
-
         $this->iconv();
     }
 

CodeIgniter/Framework/core/Common.php

@@ -846,7 +846,7 @@ function set_status_header($code = 200, $text = '')
 			}
 		}
 
-		if (strpos(PHP_SAPI, 'cgi') === 0) {
+		if (PHP_SAPI === "cgi") {
 			header('Status: ' . $code . ' ' . $text, true);
 			return;
 		}

Core/core/Http/HttpCurl.php

@@ -801,7 +801,7 @@ public function execute()
         }
 
         // Success
-        curl_close($this->session);
+        unset($this->session);
         $this->lastResponse = $this->processResponse($this->lastResponseRaw);
         $this->reset();
         $this->hasError = false;
@@ -849,7 +849,7 @@ private function handleError()
         $this->errorString = curl_error($this->session);
         $this->hasError = true;
 
-        curl_close($this->session);
+        unset($this->session);
         $this->reset();
     }