mail 接线两处收紧:入站线程取根不取最近一跳(否则跑一个来回①级归属就落空);附件没给 uploadRef 当场判 invalid,不静默丢掉

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TM4kUBvekALu9qqmp7D3wr

apps/api/src/app/mail-wiring.ts

@@ -18,9 +18,18 @@ import {
 } from '@modules/mail';
 import type { ToolHandler } from '@modules/toolbox';
 
-/** mail 的入站详情 → channel 的 InboundMail:只带存下来的附件;线程 = In-Reply-To ⊃ References 末项 */
+/**
+ * mail 的入站详情 → channel 的 InboundMail:只带存下来的附件。
+ *
+ * **线程取的是根,不是最近一跳**:我方出站登记的 threadId 恒是这一串的**首封**
+ * (`channelTransport` 回的是 `input.threadId ?? messageId`,channel 据此 `recordOutbound`),
+ * 而归属解析①级是精确等值比对。若这里取 `inReplyTo`(最近一跳),跑一个来回就漂:
+ * 我方 M1 → 客户回 M1(命中)→ 我方再回(实际 M2、仍记在 M1 名下)→ 客户回 M2 →
+ * 取到 M2,而库里从没记过 M2 ⇒ ①级落空,退到③地址+时间窗。
+ * `references[0]` 才稳定:客户端续链时首项恒是首封;客户端只给 In-Reply-To 时退回它。
+ */
 export function toInboundMail(mail: MailInboundDetail): InboundMail {
-  const threadId = mail.inReplyTo ?? mail.references.at(-1);
+  const threadId = mail.references[0] ?? mail.inReplyTo ?? undefined;
   return {
     messageId: mail.messageId,
     ...(threadId === undefined ? {} : { threadId }),
@@ -80,7 +89,8 @@ function attachmentsOf(value: unknown): MailSendInput['attachments'] {
     if (typeof v !== 'object' || v === null) return [];
     const a = v as Record<string, unknown>;
     const uploadRef = typeof a['uploadRef'] === 'string' && a['uploadRef'] !== '' ? a['uploadRef'] : undefined;
-    if (uploadRef === undefined) return [];
+    // 没给 uploadRef 的附件**不静默丢掉**:活动说「带上 q.pdf」,信发了附件没了还回 queued:true,是界面撒谎
+    if (uploadRef === undefined) throw new MailSendInvalidError([`附件 ${String(a['name'] ?? '(无名)')} 没给 uploadRef`]);
     const name = typeof a['name'] === 'string' && a['name'] !== '' ? a['name'] : uploadRef;
     return [{ name, contentType: 'application/octet-stream', uploadRef }];
   });