Intermediate — force a disk alert

Band: Intermediate
Setup: examples/disk-alert.sh in this module.

Task: Run it so you see an ALERT line, then run it with the default threshold.

Hint: THRESHOLD=0 makes every real filesystem “over.” Read the awk in the script.

Success: Forced run prints ALERT: … is N% full (threshold 0%). Default run exits 0 and prints nothing unless a mount is actually over 80%.