mcs 측정 파라미터 쓰기 응답 rcs 포맷 수정

- 기존과 동일하게 TAG 4B + freq, cycles, avg, delay, samples echo 응답

src/parser.c

@@ -1003,8 +1003,15 @@ static int cmd_mcs(const uint8_t *data, uint8_t data_len)
     }
 
     g_piezo_config = cfg;
-    int err = piezo_config_save();
-    send_response_u16("rcs:", (err == 0) ? 0U : 0xFFFD);
+    int err = app_nvs_save_piezo(&g_piezo_config);
+    if (err)
+    {
+        send_response_piezo_config("rcs:", 0xFFFD, cfg.cycles, cfg.avg, cfg.delay_us, cfg.samples);
+        piezo_config_log("[CMD] mcs save fail", &g_piezo_config);
+        return 1;
+    }
+
+    send_response_piezo_config("rcs:", g_piezo_config.freq, g_piezo_config.cycles, g_piezo_config.avg, g_piezo_config.delay_us, g_piezo_config.samples);
     piezo_config_log("[CMD] mcs saved", &g_piezo_config);
     return 1;
 }