Try this JSONata expression
[{"id":"c9893796.08e33","type":"inject","z":"c791cbc0.84f648","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"ArmyOfThings\":17,\"DiscCheerlights\":4,\"EchoCheerlights\":3,\"CympleRobot\":7,\"cymplecy\":1}","payloadType":"json","x":120,"y":1220,"wires":[["4adc95cf.27063c"]]},{"id":"4adc95cf.27063c","type":"change","z":"c791cbc0.84f648","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"($labels := [$keys($$.payload)];\t[{\t \"series\": [],\t \"data\": [[$labels.$lookup($$.payload, $)]] ,\t \"labels\": [$labels.$substring(0,10)]\t}]\t)","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":350,"y":1180,"wires":[["1dcd707332701bf2","5f2157d0.903098"]]},{"id":"5f2157d0.903098","type":"ui_chart","z":"c791cbc0.84f648","name":"","group":"8b5cde76.edd58","order":9,"width":0,"height":0,"label":"chart","chartType":"bar","legend":"false","xformat":"HH:mm:ss","interpolate":"step","nodata":"","dot":false,"ymin":"","ymax":"","removeOlder":"1","removeOlderPoints":"5","removeOlderUnit":"3600","cutout":0,"useOneColor":false,"useUTC":false,"colors":["#000000","#aec7e8","#ff7f0e","#2ca02c","#98df8a","#d62728","#ff9896","#9467bd","#c5b0d5"],"outputs":1,"useDifferentColor":false,"x":690,"y":1040,"wires":[[]]},{"id":"8b5cde76.edd58","type":"ui_group","name":"default","tab":"8f03e639.85956","order":1,"disp":false,"width":"12","collapse":false},{"id":"8f03e639.85956","type":"ui_tab","name":"Home","icon":"dashboard","order":2,"disabled":false,"hidden":false}]
expression
(
$labels := [$keys($$.payload)];
[
{
"series": [],
"data": [[$labels.$lookup($$.payload, $)]] ,
"labels": [$labels.$substring(0,10)]
}
]
)