Fix parsing of httponly cookies

Parse cookies with #HttpOnly_ prefix according to the Netscape
cookie file format specification. Previously, all lines starting
with # were treated as comments, but lines starting with #HttpOnly_
indicate cookies with the HttpOnly attribute set.

The fix:
- Detects #HttpOnly_ prefix and strips it before parsing
- Adds httponly attribute to the cookie string
- Continues to treat regular # lines as comments

See: https://curl.se/docs/http-cookies.html

Fixes #133

Author: aszenz

lib/Adapter/Artax/NetscapeCookieFileJar.php

@@ -69,7 +69,14 @@ private function parse(string $line): ?ResponseCookie
             return null;
         }
 
-        if ($line[0] === '#') {
+        // Handle httponly cookies - lines starting with #HttpOnly_ should be parsed
+        // See: https://curl.se/docs/http-cookies.html
+        $isHttpOnly = false;
+        if (str_starts_with($line, '#HttpOnly_')) {
+            $line = substr($line, 10); // Remove the '#HttpOnly_' prefix
+            $isHttpOnly = true;
+        } elseif ($line[0] === '#') {
+            // Regular comment line, skip it
             return null;
         }
 
@@ -104,6 +111,10 @@ private function parse(string $line): ?ResponseCookie
             $string .= '; secure';
         }
 
+        if ($isHttpOnly) {
+            $string .= '; httponly';
+        }
+
         return ResponseCookie::fromHeader($string);
     }
 }