Serve reset-failed and wanted-by in the systemd module (hq issue 332)

So a leftover unit's trigger is found and its failed record cleared
through the seat, not a shell: wanted-by reads the manager's reverse
dependencies and the enable links naming the unit, saying which dangle.

modules/systemd/cmd/systemd-tools/main.go

@@ -1,6 +1,6 @@
-// systemd's tools: the node-service-manager seat's nine verbs — the units on this machine in both scopes,
-// read and acted on by name, their journal, and what has failed (novox/hq ADR 0177). The node
-// tools runtime launches this bundle as a process of its own and serves what it serves (ADR 0188, ADR 0193);
+// systemd's tools: the node-service-manager seat's eleven verbs — the units on this machine in both scopes,
+// read and acted on by name, their journal, what has failed, what wants a unit, and a failed record cleared
+// (novox/hq ADR 0177, issue 332). The node tools runtime launches this bundle as a process of its own and serves what it serves (ADR 0188, ADR 0193);
 // it runs as the operator account, so acts on the system manager, and reads of its journal, escalate with
 // sudo -n, and the user scope is the account's own manager (client.go). The host applies units; this answers
 // about them. stdout is the MCP channel; this says nothing else.
@@ -123,6 +123,28 @@ func tools(m *Manager) []stdio.Tool {
 				}
 				return m.Journal(scope, unit, q)
 			}},
+		// **Clearing a failed record** (novox/hq issue 332): a unit whose file is gone keeps its failed state,
+		// and its start-limit count, in its manager until it is reset. A unit's name is required, so the
+		// verb never resets every failed unit at once.
+		act("reset-failed", "Clear one unit's failed record in its manager — its failed state and its start-limit count — and answer its state after. It removes no file and starts nothing."),
+		{Name: seat + ".wanted-by",
+			Description: "What wants, requires or triggers one unit, read-only: the manager's reverse dependencies " +
+				"(WantedBy, RequiredBy, UpheldBy, BoundBy, TriggeredBy and the rest, and the units that pull those in) and every " +
+				"enable link naming it in the scope's configuration directories (*.wants, *.requires, *.upholds) — the " +
+				"operator account's own ~/.config/systemd/user in user scope — each with where it points, whether it " +
+				"dangles and whose directory it is in; and what that means, in words.",
+			Input: map[string]any{"scope": scopeArg, "unit": unitArgS},
+			Run: func(a map[string]any) (any, error) {
+				scope, err := scopeOf(a)
+				if err != nil {
+					return nil, err
+				}
+				unit, err := unitOf(a)
+				if err != nil {
+					return nil, err
+				}
+				return m.WantedBy(scope, unit)
+			}},
 		// Was the module's own systemd_failed; on the seat since the operator's direction of 2026-10-07, so
 		// whatever holds the role answers it and every machine is asked the same way.
 		{Name: seat + ".failed",
@@ -157,7 +179,12 @@ func fromEnv() *Manager {
 			uid = n
 		}
 	}
-	return &Manager{Account: account, UID: uid, User: name, Run: execRunner, Read: readFile, Env: os.Environ()}
+	home := strings.TrimSpace(os.Getenv("MESH_OPERATOR_HOME"))
+	if home == "" && account == name {
+		home, _ = os.UserHomeDir()
+	}
+	return &Manager{Account: account, UID: uid, User: name, Run: execRunner, Read: readFile, Env: os.Environ(),
+		Home: home, ReadDir: readDir}
 }
 
 func main() {