So- basically she couldn't win today once she had a paddy! Now she will dress to go to soft play, you won't take her.
So, to get attention (positive, negative, it's all the same) she will just create again tomorrow!
I would have carried on with the day normally, and once she was dressed, let her do the normal things like go to soft play. Once you get into a cycle of punishment, she won't give in, she'll just have a paddy tomorrow as well.
I'd just leave her clothes out and say 'remember, if you want to stay with no clothes in your bedroom, fine, but if you want to come with us to the park/soft play/downstairs to see Granny then you need to have clothes on, I'll leave you to it'. She'll then get dressed.
I could be projecting though, my dd was like this at 6, just awful, would only wear one outfit, said everything 'hurt', cried and fussed a lot over clothes, it turned out in the end she was lactose intolerant and her tummy really did hurt a lot. I just assumed she was being a fuss-pot. So, don't rule out a physical reason (cold, not having eaten breakfast) which is also making things worse.
I reckon if you are calm, lay out the choice (not dressed=dont go anywhere, dressed=able to have fun, go out, do cooking (as you can't cook if you dont' have clothes on, too dangerous to splash yourself)) then she will eventually get back into wearing clothes!