fix(outlook): 多项修复与优化

- imap_new: 连接池并发安全（锁外建连、占位防重复）、IDLE tag 改用独立计数器避免私有API、get_recent_emails 新增 since_minutes 参数
- service.py: 同步更新
- accounts.py: Outlook 收件箱配置按 email 不区分大小写匹配、不受 enabled 限制
- settings.js: Outlook 批量导入前端校验要求四字段且 client_id/refresh_token 非空

src/web/routes/accounts.py

@@ -1028,9 +1028,11 @@ def _build_inbox_config(db, service_type, email: str) -> dict:
         EmailServiceModel.enabled == True
     )
     if service_type == EST.OUTLOOK:
-        # 按 config.email 匹配账号 email
-        services = query.all()
-        svc = next((s for s in services if (s.config or {}).get("email") == email), None)
+        # 按 config.email 精确匹配，不受 enabled 限制（收件箱是账号自己的邮箱）
+        all_outlook = db.query(EmailServiceModel).filter(
+            EmailServiceModel.service_type == db_type
+        ).all()
+        svc = next((s for s in all_outlook if (s.config or {}).get("email", "").lower() == email.lower()), None)
     else:
         svc = query.order_by(EmailServiceModel.priority.asc()).first()