fix: use original email From header for reply address instead of AI output

- send_summary now accepts original_sender (raw From header)
- Context stores original_sender separately from AI-generated sender
- _do_send_reply tries original_sender first, then AI sender fallback

src/tg_bot.py

@@ -21,7 +21,8 @@ _conversations: dict[int, dict] = {}
 
 @retry()
 def send_summary(tg_cfg: TelegramConfig, chat_id: str, summary_text: str,
-                 summary_data: dict, original_body: str, account_idx: int) -> int:
+                 summary_data: dict, original_body: str, account_idx: int,
+                 original_sender: str = "") -> int:
     can_reply = summary_data.get("can_reply", True)
     result = _tg_req(tg_cfg, "sendMessage", {
         "chat_id": chat_id,
@@ -34,6 +35,7 @@ def send_summary(tg_cfg: TelegramConfig, chat_id: str, summary_text: str,
         "summary_text": summary_text,
         "summary_data": summary_data,
         "original_body": original_body[:10000],
+        "original_sender": original_sender or summary_data.get("sender", ""),
         "account_idx": account_idx,
         "sender": summary_data.get("sender", ""),
         "subject": summary_data.get("subject", ""),
@@ -381,7 +383,9 @@ def _do_send_reply(tg_cfg: TelegramConfig, cfg: Config,
     if not acct.smtp:
         send_text(tg_cfg, str(chat_id), "❌ 该邮箱未配置 SMTP，无法发送回复。")
         return
-    to_addr = parseaddr(ctx["sender"])[1]
+    to_addr = parseaddr(ctx["original_sender"])[1]
+    if not to_addr:
+        to_addr = parseaddr(ctx["sender"])[1]
     if not to_addr:
         to_addr = ctx["sender"]
     subject = ctx["subject"]