fix: path segments and query params combined

[pReya]

closes #1058

• When visiting a subpath of an external site whose URL contains query parameters (e.g. ?jwt={jwt}), the path was naively concatenated onto the full URL string, producing malformed URLs like https://example.com/app?jwt=TOKEN/some/path
• The URL is now properly parsed with parse_url() so the path is inserted before the query string, producing https://example.com/app/some/path?jwt=TOKEN