nostrudel can do this stuff too

not sure about pre-signing separate to publishing tho, i think it does sign/publish in one step, click on the "more" item on the sidebar to see it... i forget ... event publisher and event console, one is for write, the other for read... it also lints the syntax on your json, generally speaking the publisher you have to remove the id and sig fields and you usually want to also remove the created_at so it is updated to the moment you click send (or YOLO as it sometimes is labeled as i've seen)