fix(scale): 修复主设备无法发现子设备及IP显示未知的问题

- UdpBroadcastReceiver 补充 socket.broadcast=true，修复广播包被内核丢弃
- MdnsDiscoveryManager 改为串行解析队列，修复多设备并发解析报 FAILURE_ALREADY_ACTIVE
- ScaleWebSocketServer 推送数据时动态填充本机 IP，解决子设备 IP 始终显示未知

app/src/main/java/com/shuwei/dish/match/scale/MdnsDiscoveryManager.kt

@@ -4,10 +4,14 @@ import android.content.Context
 import android.net.nsd.NsdManager
 import android.net.nsd.NsdServiceInfo
 import android.util.Log
+import java.util.LinkedList
 
 /**
  * mDNS 设备发现管理器（仅主设备运行）
  * 持续扫描局域网，发现或丢失 DishMatch 子设备时通过回调通知连接管理器
+ *
+ * 注意：Android NsdManager.resolveService 不支持并发调用，多台子设备同时被发现时
+ * 会报 FAILURE_ALREADY_ACTIVE(3) 导致解析失败。此处使用串行队列逐一解析。
  */
 class MdnsDiscoveryManager(private val context: Context) {
 
@@ -22,6 +26,11 @@ class MdnsDiscoveryManager(private val context: Context) {
     private var discoveryListener: NsdManager.DiscoveryListener? = null
     private var isDiscovering = false
 
+    /** 待解析队列，串行处理避免并发解析失败 */
+    private val resolveQueue = LinkedList<NsdServiceInfo>()
+    @Volatile
+    private var isResolving = false
+
     /**
      * 发现新设备时的回调：(deviceId, host, port)
      */
@@ -62,7 +71,7 @@ class MdnsDiscoveryManager(private val context: Context) {
                 // 只处理 DishMatch 服务
                 if (!service.serviceName.startsWith("DishMatch-")) return
                 Log.d(TAG, "发现设备: ${service.serviceName}")
-                resolveService(service)
+                enqueueResolve(service)
             }
 
             override fun onServiceLost(service: NsdServiceInfo) {
@@ -87,18 +96,45 @@ class MdnsDiscoveryManager(private val context: Context) {
         nsdManager.resolveService(service, object : NsdManager.ResolveListener {
             override fun onResolveFailed(info: NsdServiceInfo, errorCode: Int) {
                 Log.e(TAG, "解析设备地址失败: ${info.serviceName}, errorCode=$errorCode")
+                // 解析结束（失败），继续处理队列中下一个
+                processNextResolve()
             }
 
             override fun onServiceResolved(info: NsdServiceInfo) {
                 val deviceId = info.serviceName.removePrefix("DishMatch-")
-                val host = info.host?.hostAddress ?: return
+                val host = info.host?.hostAddress ?: run {
+                    processNextResolve()
+                    return
+                }
                 val port = info.port
                 Log.d(TAG, "设备地址已解析: $deviceId -> $host:$port")
                 onDeviceFound?.invoke(deviceId, host, port)
+                // 解析结束（成功），继续处理队列中下一个
+                processNextResolve()
             }
         })
     }
 
+    /** 将待解析服务加入队列，若当前无解析任务则立即开始 */
+    @Synchronized
+    private fun enqueueResolve(service: NsdServiceInfo) {
+        resolveQueue.add(service)
+        if (!isResolving) {
+            processNextResolve()
+        }
+    }
+
+    /** 从队列取出下一个服务进行解析 */
+    @Synchronized
+    private fun processNextResolve() {
+        val next = resolveQueue.poll() ?: run {
+            isResolving = false
+            return
+        }
+        isResolving = true
+        resolveService(next)
+    }
+
     /**
      * 停止扫描，在应用退出时调用
      */
@@ -112,5 +148,9 @@ class MdnsDiscoveryManager(private val context: Context) {
             }
         }
         discoveryListener = null
+        synchronized(this) {
+            resolveQueue.clear()
+            isResolving = false
+        }
     }
 }

app/src/main/java/com/shuwei/dish/match/scale/ScaleServiceManager.kt

@@ -63,7 +63,7 @@ object ScaleServiceManager {
         Log.d(TAG, "启动秤服务, deviceId=$deviceId, role=$role")
 
         // 所有设备：启动 WebSocket 服务端 + mDNS 注册
-        wsServer = ScaleWebSocketServer(deviceId).also { it.start() }
+        wsServer = ScaleWebSocketServer(deviceId, context).also { it.start() }
         mdnsRegister = MdnsRegisterManager(context).also { it.register(deviceId) }
 
         if (role == DeviceRole.MASTER) {

app/src/main/java/com/shuwei/dish/match/scale/ScaleWebSocketServer.kt

@@ -1,7 +1,9 @@
 package com.shuwei.dish.match.scale
 
+import android.content.Context
 import android.util.Log
 import com.google.gson.Gson
+import com.shuwei.dish.match.utils.NetworkUtil
 import com.shuwei.dish.match.utils.WeightUtil
 import org.java_websocket.WebSocket
 import org.java_websocket.handshake.ClientHandshake
@@ -12,7 +14,7 @@ import java.net.InetSocketAddress
  * 秤数据 WebSocket 服务端（主设备和子设备均运行）
  * 监听 WeightUtil 回调，将本机秤数据实时推送给所有已连接的主设备客户端
  */
-class ScaleWebSocketServer(private val deviceId: String) {
+class ScaleWebSocketServer(private val deviceId: String, private val context: Context) {
 
     companion object {
         private const val TAG = "ScaleWebSocketServer"
@@ -53,7 +55,8 @@ class ScaleWebSocketServer(private val deviceId: String) {
                 address = address,
                 weight = weight,
                 state = state,
-                ts = now
+                ts = now,
+                ip = NetworkUtil.getLocalIpAddress(context)
             )
             latestData[address] = data
             broadcast(gson.toJson(data))

app/src/main/java/com/shuwei/dish/match/scale/UdpBroadcastReceiver.kt

@@ -47,7 +47,7 @@ class UdpBroadcastReceiver {
 
     private fun listenLoop() {
         try {
-            socket = DatagramSocket(UdpBroadcastSender.BROADCAST_PORT)
+            socket = DatagramSocket(UdpBroadcastSender.BROADCAST_PORT).also { it.broadcast = true }
             val buf = ByteArray(BUFFER_SIZE)
             while (running) {
                 val packet = DatagramPacket(buf, buf.size)