feat: 添加模糊查询链接编号的方法以协助调试，优化用户链接状态查询逻辑，确保线程安全并避免重复数据库查询

src/main/resources/mapper/agent/LinkTaskMapper.xml

@@ -278,6 +278,15 @@
         WHERE status = #{status}
         ORDER BY created_at ASC
     </select>
+    
+    <!-- 调试用：模糊查询链接编号 -->
+    <select id="findByCodeNoLike" resultMap="LinkTaskMap">
+        SELECT id, batch_id, agent_id, code_no, token_hash, expire_at, status, region, machine_id, login_at, refund_at, revoked_at, created_at, updated_at, need_refresh, refresh_time, qr_created_at, qr_expire_at, first_region_select_at, completed_points, completion_images, reason
+        FROM link_task
+        WHERE UPPER(code_no) LIKE UPPER(CONCAT('%', #{codeNo}, '%'))
+        ORDER BY created_at DESC
+        LIMIT 10
+    </select>
 
     <!-- 原子占用设备，避免并发下同一设备被多个链接占用 -->
     <update id="reserveDeviceIfFree">