Mail is content: a state's mail: and the invite mail, published for gdo

`mail: { to, subject, body }` on a state in aggregates.yaml sends when a
record enters that state, `to: submitter` or one address, templates
over the record's fields plus {site}, {chain}, {email}. An invite mails
its one-time link built in, reworded by `mail.invite` in site.yaml,
which also carries the sender (`mail.from`, `mail.reply_to`); without
it a site sends nothing and says so in the log. Portal renders the
text and an HTML alternative and publishes one message per state
change on portal.mail.send in the WORMHOLE stream, id <bucket>:<record>
:<state> so a retried transition sends once; uhhm/gdo holds the
durable consumer and talks SMTP. The lint requires a required email
field on every form recording into a bucket that mails the submitter.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01L4jrCgLiKKHAEFuZUJjckH

src/app.rs

@@ -2245,6 +2245,7 @@ pub async fn submit_answer(
         if let Ok(bytes) = serde_json::to_vec(&invited) {
             let _ = state.nats.publish(crate::people::INVITED_SUBJECT, bytes.into()).await;
         }
+        crate::mail::on_invite(&state, &invited).await;
     }
     // `/shape/{curve.key}`: the next page may be chosen by the answer.
     let next = match alt.action.as_deref() {
@@ -2298,6 +2299,11 @@ pub async fn submit_answer(
         {
             tracing::error!("failed to store answer in {bucket}: {e}");
         }
+        // Arrival is a state too: what the schema says the first
+        // state sends, it sends now.
+        if let Some(initial) = state.aggregates.load().get(bucket).map(|s| s.initial.clone()) {
+            crate::mail::on_state(&state, bucket, &chain_hash, &initial, &responses).await;
+        }
     }
 
     Ok(SubmitResult { next, chain_hash })