fix: accept bare Pi-hole IPv4 addresses

internal/pihole/client.go

@@ -71,7 +71,11 @@ func New(rawURL string, insecureTLS bool) (*Client, error) {
 }
 
 func normalizeBaseURL(raw string) (string, error) {
-	parsed, err := url.Parse(strings.TrimSpace(raw))
+	raw = strings.TrimSpace(raw)
+	if address := net.ParseIP(raw); address != nil && address.To4() != nil {
+		raw = "http://" + raw
+	}
+	parsed, err := url.Parse(raw)
 	if err != nil || parsed.Host == "" || (parsed.Scheme != "http" && parsed.Scheme != "https") {
 		return "", errors.New("Pi-hole-Adresse muss eine vollständige HTTP- oder HTTPS-URL sein")
 	}