feat: enhance logging detail across all modules

- email_client: log IMAP connection, login, UNSEEN count, each email
  details (subject/sender/body size), mark-as-seen progress
- ai_client: log AI request params, timing, token usage, response size
- smtp_client: log SMTP connect, login, send details
- tg_bot: log all callback actions with subject context, message states
- main: periodic queue depth report (email_queue/tg_queue/pending_uids)

main.py

@@ -116,8 +116,14 @@ def main():
     for t in threads:
         t.start()
 
+    logger.info("所有线程已启动，进入主循环")
+    tick = 0
     try:
         while _running:
+            tick += 1
+            if tick % 30 == 0:
+                logger.info("队列状态: email_queue=%d tg_queue=%d pending_uids=%d",
+                            _email_queue.qsize(), _tg_queue.qsize(), len(_pending_uids))
             time.sleep(1)
     except KeyboardInterrupt:
         _running = False