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/summarizer.py

@@ -31,6 +31,7 @@ def ai_process(cfg: Config, acct_idx: int, mail: Email) -> Optional[dict]:
         "text": text,
         "data": summary,
         "original_body": mail.body,
+        "original_sender": mail.sender,
         "acct_idx": acct_idx,
         "uid": mail.uid,
     }
@@ -40,6 +41,7 @@ def tg_send_and_mark(cfg: Config, info: dict):
     acct = cfg.email_accounts[info["acct_idx"]]
     send_summary(cfg.telegram, cfg.telegram.chat_id,
                  info["text"], info["data"],
-                 info["original_body"], info["acct_idx"])
+                 info["original_body"], info["acct_idx"],
+                 original_sender=info.get("original_sender", ""))
     mark_as_seen(acct, [info["uid"]])
     logger.info(f"  已发送并标记已读")