feat: ADC 로그 저장 + 기기정보 mid? + LED 모드 + 무한 3초 reconnect

1. ADC 로그: 측정 완료 시 MeasurementLogService.logMeasurement() 호출
   → 6채널 raw ADC + 채널별 ant/post/score 저장 (JSONL)

2. 기기 정보: 연결 직후 mid? 전송 → rid: 응답 파싱 → 로그 기록
   (HW Version, Serial Number, FW Version 일괄 조회)

3. LED 모드: Placement Guide 연동
   - 스캔 시작 → mls?(5) ALIGN_SEARCHING
   - PASS → mls?(6) ALIGN_COMPLETE
   - 스캔 종료 → mls?(0) OFF

4. Reconnect: 3/5/10초 5회 → 3초 간격 무한 재시도
   (연결됐다가 끊어진 경우, 사용자가 Home 돌아갈 때까지)

5. BLE 로그: mid/mls TX 파싱, rid:/rls: RX 파싱 추가

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/src/main/java/com/example/medilightv2android/ble/BleManager.kt

@@ -60,8 +60,7 @@ class BleManager private constructor(private val context: Context) {
     var lastConnectedAddress: String? = null
         private set
     private var reconnectAttempt = 0
-    private val maxReconnectAttempts = 5
-    private val reconnectDelays = longArrayOf(3000, 5000, 10000, 10000, 10000)
+    private val reconnectIntervalMs: Long = 3000
     private var reconnectTimer: Runnable? = null
     private var lastRxTimestamp: Long = 0
     private var watchdogTimer: Runnable? = null
@@ -281,6 +280,8 @@ class BleManager private constructor(private val context: Context) {
             "mqq" -> "NIRS activate"
             "mag" -> "NIRS gain query"
             "mcj" -> "NIRS MCJ query"
+            "mid" -> "device info query"
+            "mls" -> "LED mode ${if (data.size > 4) data[4].toInt() and 0xFF else "?"}"
             else -> ""
         }
         logd { "sendRaw: $cmdPreview (${data.size} bytes)" }
@@ -344,6 +345,14 @@ class BleManager private constructor(private val context: Context) {
         sendRaw(CRC16.buildCommand("msn", intArrayOf(0)))
     }
 
+    fun sendDeviceInfoQuery() {
+        sendRaw(CRC16.buildCommand("mid"))
+    }
+
+    fun sendLedMode(state: Int) {
+        sendRaw(CRC16.buildCommand("mls", intArrayOf(state)))
+    }
+
     fun startBatteryPolling() {
         batteryTimer?.let { handler.removeCallbacks(it) }
         sendBatteryQuery()
@@ -437,23 +446,14 @@ class BleManager private constructor(private val context: Context) {
     // ── Auto Reconnect ──
 
     private fun scheduleAutoReconnect() {
-        if (reconnectAttempt >= maxReconnectAttempts) {
-            logw { "Max reconnect attempts ($maxReconnectAttempts) reached" }
-            debugLogger.reconnectFailed()
-            isReconnecting.value = false
-            onReconnectionFailed?.invoke()
-            return
-        }
-
-        val delay = reconnectDelays[reconnectAttempt.coerceAtMost(reconnectDelays.size - 1)]
-        logd { "Auto-reconnect attempt ${reconnectAttempt + 1}/$maxReconnectAttempts in ${delay}ms" }
-        debugLogger.reconnecting(reconnectAttempt + 1, maxReconnectAttempts, delay)
+        logd { "Auto-reconnect attempt ${reconnectAttempt + 1} in ${reconnectIntervalMs}ms" }
+        debugLogger.reconnecting(reconnectAttempt + 1, -1, reconnectIntervalMs)
         isReconnecting.value = true
 
         cancelReconnectTimer()
         val timer = Runnable { attemptAutoReconnect() }
         reconnectTimer = timer
-        handler.postDelayed(timer, delay)
+        handler.postDelayed(timer, reconnectIntervalMs)
     }
 
     private var reconnectScanCallback: ScanCallback? = null
@@ -522,13 +522,9 @@ class BleManager private constructor(private val context: Context) {
             try { scanner.stopScan(callback) } catch (_: Exception) {}
             reconnectScanCallback = null
 
-            if (!isConnected.value && reconnectAttempt < maxReconnectAttempts) {
-                debugLogger.warn("RECONNECT_SCAN_TIMEOUT #$reconnectAttempt — device not found")
+            if (!isConnected.value) {
+                debugLogger.warn("RECONNECT_SCAN_TIMEOUT #$reconnectAttempt — device not found, retrying...")
                 scheduleAutoReconnect()
-            } else if (!isConnected.value) {
-                debugLogger.reconnectFailed()
-                isReconnecting.value = false
-                onReconnectionFailed?.invoke()
             }
         }, 8000)
     }
@@ -699,6 +695,7 @@ class BleManager private constructor(private val context: Context) {
                             isServiceReady.value = true
                             startBatteryPolling()
                             startWatchdog()
+                            sendDeviceInfoQuery()
                             logd { "Service ready! (CCCD written)" }
                         }
                     } else {
@@ -783,6 +780,15 @@ class BleManager private constructor(private val context: Context) {
                     debugLogger.rx("rsn", data.size, "battery=${millivolts}mV (${pct}%)")
                 }
             }
+            "rid:" -> {
+                val info = if (data.size > 4) String(data, 4, data.size - 4, Charsets.US_ASCII).trim() else "?"
+                debugLogger.rx("rid", data.size, "device_info=$info")
+                debugLogger.info("DEVICE_INFO $info")
+            }
+            "rls:" -> {
+                val state = if (data.size >= 5) data[4].toInt() and 0xFF else -1
+                debugLogger.rx("rls", data.size, "led_state=$state")
+            }
             else -> {
                 val hex = data.take(8).joinToString(" ") { "%02X".format(it) }
                 debugLogger.rx("???", data.size, "unknown prefix='$prefix' hex=$hex")