better tracking of first announce seen (#502)

app/src/main/java/com/bitchat/android/mesh/BluetoothConnectionTracker.kt

@@ -30,6 +30,8 @@ class BluetoothConnectionTracker(
     private val connectedDevices = ConcurrentHashMap<String, DeviceConnection>()
     private val subscribedDevices = CopyOnWriteArrayList<BluetoothDevice>()
     val addressPeerMap = ConcurrentHashMap<String, String>()
+    // Track whether we have seen the first ANNOUNCE on a given device connection
+    private val firstAnnounceSeen = ConcurrentHashMap<String, Boolean>()
     
     // RSSI tracking from scan results (for devices we discover but may connect as servers)
     private val scanRSSI = ConcurrentHashMap<String, Int>()
@@ -91,6 +93,8 @@ class BluetoothConnectionTracker(
         Log.d(TAG, "Tracker: Adding device connection for $deviceAddress (isClient: ${deviceConn.isClient}")
         connectedDevices[deviceAddress] = deviceConn
         pendingConnections.remove(deviceAddress)
+        // Mark as awaiting first ANNOUNCE on this connection
+        firstAnnounceSeen[deviceAddress] = false
     }
     
     /**
@@ -280,6 +284,7 @@ class BluetoothConnectionTracker(
             addressPeerMap.remove(deviceAddress)
         }
         pendingConnections.remove(deviceAddress)
+        firstAnnounceSeen.remove(deviceAddress)
         Log.d(TAG, "Cleaned up device connection for $deviceAddress")
     }
     
@@ -313,6 +318,21 @@ class BluetoothConnectionTracker(
         addressPeerMap.clear()
         pendingConnections.clear()
         scanRSSI.clear()
+        firstAnnounceSeen.clear()
+    }
+
+    /**
+     * Mark that we have received the first ANNOUNCE over this device connection.
+     */
+    fun noteAnnounceReceived(deviceAddress: String) {
+        firstAnnounceSeen[deviceAddress] = true
+    }
+
+    /**
+     * Check whether the first ANNOUNCE has been seen for a device connection.
+     */
+    fun hasSeenFirstAnnounce(deviceAddress: String): Boolean {
+        return firstAnnounceSeen[deviceAddress] == true
     }
     
     /**