I’m afraid you currently don’t have enough space to start docker, which you would need to then run ./launcher cleanup (which would be the preferred way to tidy up any old containers/images leftover from previous rebuilds). Ideally, you’d also want your site to be live (./launcher start app) before you run it, so you have a fallback if anything goes awry with the rebuild.
I haven’t had a site that’s 100% full, so it’s a little unclear to me what may or may not work (autoclean and autoremove not being able to run, for instance). @Benjamin_D Do you know if it’s still possible to manually remove some files to free up a bit of space to get the ball rolling? eg.
cd /var/discourse/shared/standalone/backups/default dir
Copy the oldest file name, and then paste to remove it eg:
rm jammydodger-s-test-site-2022-04-12-033748-v20220407195246.tar.gz
Or possibly check for orphaned images and remove one or more of those:
docker images
Though it’s probably also worth mentioning that if your site has a lot of user uploads it may be that you simply need to resize. But if you haven’t done any server maintainence since you started, there’s a good chance a tidy up should tide you over for a while.