[php-src] PR #24120: Replace php_stream_wrapper.is_url with flags and resolve nested wrappers

Pull Request: https://github.com/php/php-src/pull/24120 Author: bukka The compress.zlib:// and compress.bzip2:// wrappers open the path that follows their scheme through the stream layer, so whether such a stream is local depends on the inner wrapper. stream_is_local() and the openssl cafile check treated them as always local. Replace the is_url field with a flags field. PHP_STREAM_WRAPPER_FLAG_URL keeps the value 1 so existing initializers are unchanged, and the new PHP_STREAM_WRAPPER_FLAG_NESTED marks wrappers that open the remainder of the path. php_stream_wrapper_is_url() walks nested schemes in a loop for path strings, and PHP_STREAM_FLAG_URL is set on opened streams, copied from the inner stream by nested wrappers, so php_stream_is_url() needs no lookup. The open path and the allow_url_fopen enforcement at the inner open are unchanged.