Keep a published rule when some invitation emails already went out, and only set Reply-To when the inviter address is a mailbox.

lib/server/mail.ts

@@ -8,6 +8,7 @@ import {
 import { getSmtpUrl } from "./env";
 import {
   buildRuleStakeholderInviteMail,
+  stakeholderInviteReplyTo,
   type RuleStakeholderInviteMailInput,
 } from "./ruleStakeholderInviteMail";
 
@@ -102,12 +103,13 @@ export async function sendRuleStakeholderInviteEmail(
   input: RuleStakeholderInviteMailInput,
 ): Promise<void> {
   const { subject, text, html } = buildRuleStakeholderInviteMail(input);
+  const replyTo = stakeholderInviteReplyTo(input.inviterEmail);
   await sendHtmlMail({
     to: input.to,
     subject,
     text,
     html,
-    replyTo: input.inviterEmail.trim().toLowerCase(),
+    ...(replyTo ? { replyTo } : {}),
     devLog: `[dev] Rule stakeholder invite (${input.communityName}) for ${input.to}: ${input.verifyUrl}`,
   });
 }