docs: wrap service in service.go with Helm values conditional for katenary.v3/svc-optional label

Co-authored-by: aider (ollama_chat/gpt-oss:120b) <aider@aider.chat>

internal/generator/service.go

@@ -84,6 +84,7 @@ func (s *Service) Yaml() ([]byte, error) {
 		return nil, err
 	}
 
+	// Remove any loadBalancer lines that may have been added unintentionally.
 	lines := []string{}
 	for line := range strings.SplitSeq(string(y), "\n") {
 		if regexp.MustCompile(`^\s*loadBalancer:\s*`).MatchString(line) {
@@ -93,5 +94,19 @@ func (s *Service) Yaml() ([]byte, error) {
 	}
 	y = []byte(strings.Join(lines, "\n"))
 
+	// If the service has the label "katenary.v3/svc-optional", wrap the output
+	// with a Helm values conditional.
+	if s.service != nil && s.service.Labels != nil {
+		if _, ok := s.service.Labels["katenary.v3/svc-optional"]; ok {
+			// Ensure we have a trailing newline before appending the closing block.
+			content := string(y)
+			if !strings.HasSuffix(content, "\n") {
+				content += "\n"
+			}
+			content = "{{- if .Values.service.enabled }}\n" + content + "{{- end }}\n"
+			y = []byte(content)
+		}
+	}
+
 	return y, err
 }