fix(ops): don't imply the current sha was itself deployed

A non-site-only skip advances the recorded sha without a production deploy,
so 'deployed Nm ago' could read as if that sha was deployed. Say 'last
production deploy Nm ago' instead.

scripts/ops-health.sh

@@ -121,7 +121,7 @@ case "$last_epoch" in ''|*[!0-9]*) last_epoch=0 ;; esac
 
 if [ "$deployed" = "$origin" ] && [ "$origin" != "none" ]; then
   if [ "$last_epoch" -gt 0 ]; then
-    p "  ${G}✓${N} live is current (${origin:0:9}), deployed $(human_age $((now - last_epoch))) ago"
+    p "  ${G}✓${N} live is current (${origin:0:9}) — last production deploy $(human_age $((now - last_epoch))) ago"
   else
     p "  ${G}✓${N} live is current (${origin:0:9})"
   fi