fix(auth): extend stream-based HTTP to POST requests in OidcHttpGateway

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

core/Service/Auth/OidcHttpGateway.php

@@ -11,32 +11,41 @@ class OidcHttpGateway
      */
     public function call(string $method, string $url, mixed $data = '', array $headers = []): array
     {
-        if (strtoupper($method) === 'GET') {
+        return $this->callWithStream(strtoupper($method), $url, $data, $headers);
-            return $this->getWithStream($url, $headers);
-        }
-        return Curl::call($method, $url, $data, $headers);
     }
 
     /**
      * @param array<string, string> $headers
      */
-    private function getWithStream(string $url, array $headers): array
+    private function callWithStream(string $method, string $url, mixed $data, array $headers): array
     {
         $headerLines = [];
         foreach ($headers as $key => $value) {
             $headerLines[] = $key . ': ' . $value;
         }
+
+        $httpContext = [
+            'method' => $method,
+            'header' => implode("\r\n", $headerLines),
+            'ignore_errors' => true,
+        ];
+
+        if ($method === 'POST') {
+            $body = is_array($data) ? http_build_query($data) : (string) $data;
+            $httpContext['content'] = $body;
+            if (!isset($headers['Content-Type'])) {
+                $httpContext['header'] .= "\r\nContent-Type: application/x-www-form-urlencoded";
+            }
+        }
+
         $ctx = stream_context_create([
-            'http' => [
+            'http' => $httpContext,
-                'method' => 'GET',
-                'header' => implode("\r\n", $headerLines),
-                'ignore_errors' => true,
-            ],
             'ssl' => [
                 'verify_peer' => true,
                 'verify_peer_name' => true,
             ],
         ]);
+
         $body = @file_get_contents($url, false, $ctx);
         $status = 0;
         $responseHeaders = [];