Open every explanation with what the operator needs to do, and offer the answers

The operator could not tell from a notification whether to act, and was told to
have an agent do it. Each condition now says "Nothing for you to do." or
"Needs you:" with one thing they can do themselves, and carries the actions the
operator channel performs when chosen (hq ADR 0253).

cmd/mesh-controller/machine_units.go

@@ -117,8 +117,10 @@ func machineUnitsObservation(node string, u *link.UnitsHealth) (conditions.Obser
 		failed = fmt.Sprintf("%d failed services", len(u.Failed))
 	}
 	o.Headline = fmt.Sprintf("%s on %s", conditions.Capital(failed), node)
-	o.Explanation = fmt.Sprintf("On %s, %s failed. No module manages them, so the mesh does not repair them: mend or "+
-		"remove them on %s.", node, namesWords(plain, 3), node)
+	o.Needs = fmt.Sprintf("mend or remove them on %s, or silence this if they do not matter.", node)
+	o.Explanation = fmt.Sprintf("On %s, %s failed. No module manages them, so the mesh does not repair them.",
+		node, namesWords(plain, 3))
+	o.Actions = []conditions.Action{conditions.SilenceAction(o.Key())}
 	o.Resolved = "No failed services on " + node + " any more"
 	return o, true
 }