Node software build checks now free disk space and drop debug info

One change landed in the software that runs the nodes of Satsuma's chain. That software is built with the Polkadot SDK, and every change to it is compiled and tested automatically by CI before it is accepted. The change makes the CI job free disk space on its runner and drop debug info from the build. It was squash-merged into main in a Claude Code session.

The same fix passed CI on its branch before the merge. After the merge the branch was deleted and the local copy of main was updated.

"Merging started a new CI run on main, which takes about 30 minutes." That run had not reported a result when the session ended.