feat(API): user invitations and emails

internal/infrastructure/mailer/mailRepository.go

@@ -24,14 +24,25 @@ func NewMailRepository(smtp config.SmtpSettings) *MailRepository {
 
 const defaultSubject = "RenewCMS | Action required"
 
-func (m MailRepository) Render(templateName string, data any) (string, string, error) {
-	subject := defaultSubject
+type subjectProvider interface {
+	Subject() string
+}
+
+func subjectFor(templateName string, data any) string {
+	if provider, ok := data.(subjectProvider); ok {
+		return provider.Subject()
+	}
 	switch templateName {
 	case "verification":
-		subject = "Verify your RenewCMS account"
+		return "Verify your RenewCMS account"
 	case "password-reset":
-		subject = "Reset your RenewCMS password"
+		return "Reset your RenewCMS password"
 	}
+	return defaultSubject
+}
+
+func (m MailRepository) Render(templateName string, data any) (string, string, error) {
+	subject := subjectFor(templateName, data)
 
 	tmpl, err := template.ParseFS(mailTemplateFiles, "templates/"+templateName+".html")
 	if err != nil {