Local control channel: unprivileged users can trigger --force-update via the running service

internal/control/control_other.go

@@ -0,0 +1,18 @@
+//go:build !windows && !linux
+
+package control
+
+import (
+	"context"
+	"log/slog"
+)
+
+// Serve is a no-op on platforms without a control channel.
+func Serve(ctx context.Context, h Handler, log *slog.Logger) error {
+	return ErrUnavailable
+}
+
+// Ask always reports the channel as unavailable.
+func Ask(cmd string) (string, error) {
+	return "", ErrUnavailable
+}