fix: skip already-processing UIDs at FETCH level to avoid downloading email content

src/tg_bot.py

@@ -193,7 +193,8 @@ def _summary_keyboard(can_reply: bool = True, is_promotion: bool = False, links:
     for link in (links or []):
         url = link.get("url", "")
         text = link.get("text", "打开链接")[:30]
-        if url.startswith("http"):
+        # 校验 URL：合法 http/https，无多重协议头，长度合理
+        if url.startswith("http") and url.count("://") == 1 and len(url) < 200:
             kb.append([{"text": f"🔗 {text}", "url": url}])
     return {"inline_keyboard": kb}