Show API key settings link when WHEROBOTS_API_KEY is missing

When the user hasn't set WHEROBOTS_API_KEY, the error now includes a
direct link to the console settings page (/settings#api-keys) and the
export command to configure it. The link derives its host from
WHEROBOTS_API_URL so it works with custom API hosts (e.g.
api.staging.wherobots.com → staging.wherobots.com/settings#api-keys).

Ref: EWT-4554

Author: ClayMav

internal/config/config.go

@@ -43,8 +43,8 @@ func Load() (Config, error) {
 	apiKey := strings.TrimSpace(os.Getenv(envWherobotsAPIKey))
 	if apiKey == "" {
 		return Config{}, fmt.Errorf(
-			"%s is required\n\nTo create an API key, visit: https://cloud.wherobots.com/apiKey\nThen export it:\n\n  export %s='<your-api-key>'",
-			envWherobotsAPIKey, envWherobotsAPIKey,
+			"%s is required\n\nTo create an API key, visit: %s\nThen export it:\n\n  export %s='<your-api-key>'",
+			envWherobotsAPIKey, apiKeyURL(openAPIURL), envWherobotsAPIKey,
 		)
 	}
 
@@ -125,6 +125,19 @@ func parseDuration(raw string, fallback time.Duration) (time.Duration, error) {
 	return d, nil
 }
 
+// apiKeyURL derives the console settings URL from the resolved OpenAPI spec URL.
+// It strips the "api." prefix from the host (e.g. api.cloud.wherobots.com → cloud.wherobots.com)
+// and appends /settings#api-keys.
+func apiKeyURL(openAPISpecURL string) string {
+	parsed, err := url.Parse(openAPISpecURL)
+	if err != nil {
+		return "https://cloud.wherobots.com/settings#api-keys"
+	}
+	host := parsed.Hostname()
+	host = strings.TrimPrefix(host, "api.")
+	return fmt.Sprintf("%s://%s/settings#api-keys", parsed.Scheme, host)
+}
+
 func getenvDefault(key, fallback string) string {
 	if value := os.Getenv(key); value != "" {
 		return value

internal/config/config_test.go

@@ -42,15 +42,28 @@ func TestLoadBuildsSpecURLFromWherobotsAPIURL(t *testing.T) {
 }
 
 func TestLoadRequiresWherobotsAPIKey(t *testing.T) {
-	t.Setenv("WHEROBOTS_API_URL", "https://api.example.com")
+	t.Setenv("WHEROBOTS_API_URL", "")
+	t.Setenv("WHEROBOTS_API_KEY", "")
+
+	_, err := Load()
+	if err == nil {
+		t.Fatalf("expected Load() error")
+	}
+	if !strings.Contains(err.Error(), "https://cloud.wherobots.com/settings#api-keys") {
+		t.Fatalf("error should contain default API key URL, got: %v", err)
+	}
+}
+
+func TestLoadMissingKeyUsesCustomAPIHost(t *testing.T) {
+	t.Setenv("WHEROBOTS_API_URL", "https://api.staging.wherobots.com")
 	t.Setenv("WHEROBOTS_API_KEY", "")
 
 	_, err := Load()
 	if err == nil {
 		t.Fatalf("expected Load() error")
 	}
-	if !strings.Contains(err.Error(), "https://cloud.wherobots.com/apiKey") {
-		t.Fatalf("error should contain API key URL, got: %v", err)
+	if !strings.Contains(err.Error(), "https://staging.wherobots.com/settings#api-keys") {
+		t.Fatalf("error should contain custom API key URL, got: %v", err)
 	}
 }