fix: Don't pre-create child containers - let ai user create them as needed

Changed to only prepare /var/lib/machines/ directory inside aios.
ai user will create child containers (workspace, restore-img, etc.) using machinectl as needed.

cfg/install.sh

@@ -27,7 +27,7 @@ fi
 echo "1. Extracting $TARBALL..."
 tar xf "$TARBALL"
 
-# Install aios (contains child containers inside)
+# Install aios (base container)
 echo "2. Installing aios to /var/lib/machines/..."
 rm -rf /var/lib/machines/$NAME
 mkdir -p /var/lib/machines