monitor filesystem errors for ext4

Split from #41639 (closed)

filesystem health checks, Nagios' dsa-check-filesystems, seemingly missing from the node exporter (upstream issue 3113 and 3005), workaround: check /sys/fs/ext4/*/errors_count != 0

see #41639 (comment 3146082) for prior discussion

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information