Add uptime to serial status output

Auto_Seat.ino

@@ -582,6 +582,7 @@ void printStatus(const __FlashStringHelper *tag) {
   Serial.print(F("["));
   Serial.print(tag);
   Serial.println(F("]"));
+  printUptime();
   Serial.print(F("raw="));
   Serial.print(parkingRawValue);
   Serial.print(F(" ig="));
@@ -623,6 +624,26 @@ void printStatus(const __FlashStringHelper *tag) {
   Serial.println(autoCalibrationState);
 }
 
+void printUptime() {
+  unsigned long totalMs = millis();
+  unsigned long hours = totalMs / 3600000UL;
+  totalMs %= 3600000UL;
+  unsigned long minutes = totalMs / 60000UL;
+  totalMs %= 60000UL;
+  unsigned long seconds = totalMs / 1000UL;
+  unsigned long milliseconds = totalMs % 1000UL;
+
+  Serial.print(F("uptime="));
+  Serial.print(hours);
+  Serial.print(F("h "));
+  Serial.print(minutes);
+  Serial.print(F("m "));
+  Serial.print(seconds);
+  Serial.print(F("s "));
+  Serial.print(milliseconds);
+  Serial.println(F("ms"));
+}
+
 void setRelay(int relayPin, boolean state) {
   digitalWrite(relayPin, state ? LOW : HIGH);
 }

README.md

@@ -80,6 +80,12 @@ While debug mode is active, only `x` is accepted. Other input is ignored.
 
 Manual position commands `u`, `d`, and `p` are allowed while driving, as long as the controller is not busy with an in-progress movement.
 
+Every status output includes boot uptime:
+
+```text
+uptime=0h 2m 13s 457ms
+```
+
 ## Automatic Calibration
 
 - Each `IG1 HIGH -> LOW` transition increments the EEPROM use counter.

report.html

@@ -224,6 +224,7 @@ when currentPosMs <= 0:
       </tbody>
     </table>
     <p><span class="warn">주의:</span> 명령은 한 글자만 받습니다. <code>debug</code>, <code>down</code>, <code>position 2000</code>처럼 긴 문자열은 실행하지 않습니다.</p>
+    <p>모든 상태 출력에는 부팅 후 경과 시간이 <code>uptime=0h 2m 13s 457ms</code> 형식으로 포함됩니다. debug 출력에서도 1초마다 같은 형식으로 확인할 수 있습니다.</p>
 
     <h2>5. 수동 위치 세팅 시뮬레이션</h2>
     <table>