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)

src/ai_client.py

@@ -1,9 +1,13 @@
 import json
+import logging
+import time
 from typing import Any
 import requests
 from src.config import AIConfig
 from src.retry import retry
 
+logger = logging.getLogger(__name__)
+
 SYSTEM_PROMPT = """你是一个邮件摘要助手。请分析邮件内容并以 JSON 格式返回结构化摘要。
 
 返回格式必须严格遵循以下 JSON schema：
@@ -35,6 +39,8 @@ SYSTEM_PROMPT = """你是一个邮件摘要助手。请分析邮件内容并以
 
 @retry()
 def summarize_email(ai_cfg: AIConfig, recipient: str, subject: str, sender: str, body: str) -> dict[str, Any]:
+    body_preview = body[:80].replace("\n", " ")
+    logger.info("AI 摘要请求: sender=%s subject=%s body_preview=%s", sender, subject, body_preview)
     content = f"收件人: {recipient}\n发件人: {sender}\n主题: {subject}\n正文:\n{body[:4000]}"
 
     payload = {
@@ -68,6 +74,8 @@ MORE_REPLIES_PROMPT = """你是一个邮件回复助手。根据以下邮件内
 @retry()
 def generate_more_replies(ai_cfg: AIConfig, sender: str, subject: str, body: str,
                           previous_suggestions: list[dict], user_hint: str = "") -> list[dict]:
+    logger.info("AI 换批请求: sender=%s subject=%s user_hint=%s prev=%d 条",
+                sender, subject, user_hint or "(无)", len(previous_suggestions))
     content = f"发件人: {sender}\n主题: {subject}\n正文:\n{body[:4000]}\n\n已生成过的回复:\n"
     for i, s in enumerate(previous_suggestions, 1):
         content += f"{i}. {s['text']}\n"
@@ -87,6 +95,9 @@ def generate_more_replies(ai_cfg: AIConfig, sender: str, subject: str, body: str
 
 
 def _call_deepseek(ai_cfg: AIConfig, payload: dict) -> dict:
+    model = payload.get("model", ai_cfg.model)
+    logger.info("DeepSeek API 请求: model=%s", model)
+    t0 = time.time()
     headers = {
         "Authorization": f"Bearer {ai_cfg.api_key}",
         "Content-Type": "application/json",
@@ -97,7 +108,13 @@ def _call_deepseek(ai_cfg: AIConfig, payload: dict) -> dict:
         json=payload,
         timeout=60,
     )
+    elapsed = time.time() - t0
     resp.raise_for_status()
     result = resp.json()
+    usage = result.get("usage", {})
+    prompt_tokens = usage.get("prompt_tokens", "?")
+    completion_tokens = usage.get("completion_tokens", "?")
     raw = result["choices"][0]["message"]["content"]
+    logger.info("DeepSeek API 响应: %.2fs, token=%d+%d, 输出长度=%d",
+                elapsed, prompt_tokens, completion_tokens, len(raw))
     return json.loads(raw)