pub type RenderFn = extern "C" fn(input_json: StbStringRef, out: *mut StbString, user_data: *mut c_void) -> i32;Expand description
A render/transform fn (for the renderer registrars). input_json is borrowed;
out is owning output the plugin frees via host free_string. Markdown
handlers return {markdown:"..."}; message/entry handlers return
{text:"...",markdown?:true} or {lines:["..."]} for terminal UI.