Consolidates #2, #3 and #4 with split-frame regression tests. Uses Pi's streaming JSON parser and preserves usage across empty trailers. Co-authored-by: Max19970 <maxshubert@yandex.ru> Co-authored-by: SannaMarcoDev <sannamarco.dev@gmail.com> Co-authored-by: Jeremias Volker <jeremias.volker@uniklinik-freiburg.de>