Fix Send gauges showing intensity, zero when idle

- Send gauges now show waveform intensity (0-100) not strength ceiling
- State.LastIntensityA/B tracks average intensity per tick
- Zero when no pattern/stream active (was 25 due to IntensityOff 101 sentinel)
- Recv gauges unchanged (device-reported strength 0-200)

MainForm.cs

@@ -142,7 +142,7 @@ public class MainForm : Form
             Location = new Point(72, 160),
             Size = new Size(332, 20),
             Minimum = 0,
-            Maximum = 200,
+            Maximum = 100,
             Style = ProgressBarStyle.Continuous
         };
         _lblSendB = new Label
@@ -157,7 +157,7 @@ public class MainForm : Form
             Location = new Point(72, 184),
             Size = new Size(332, 20),
             Minimum = 0,
-            Maximum = 200,
+            Maximum = 100,
             Style = ProgressBarStyle.Continuous
         };
         _lblRecvA = new Label
@@ -357,8 +357,8 @@ public class MainForm : Form
         _lblBle.Text = _device.IsConnected
             ? $"BLE: connected ({_device.DeviceName})"
             : "BLE: disconnected";
-        _gaugeSendA.Value = Math.Clamp(_state.LastSentA, 0, 200);
-        _gaugeSendB.Value = Math.Clamp(_state.LastSentB, 0, 200);
+        _gaugeSendA.Value = Math.Clamp(_state.LastIntensityA, 0, 100);
+        _gaugeSendB.Value = Math.Clamp(_state.LastIntensityB, 0, 100);
         _gaugeRecvA.Value = Math.Clamp(_device.StrengthA, 0, 200);
         _gaugeRecvB.Value = Math.Clamp(_device.StrengthB, 0, 200);
         _btnTest.Enabled = !_server.HasClient && !IsTestRunning;

State.cs

@@ -17,6 +17,7 @@ public class State
 
     public int ActualA, ActualB;
     public int LastSentA, LastSentB;
+    public int LastIntensityA, LastIntensityB;
 
     public int MaxStrength = 200;
     public LimitMode LimitMode = LimitMode.Clamp;
@@ -105,9 +106,14 @@ public class State
             DirtyA = false;
             DirtyB = false;
 
+            bool hasA = !StreamA.IsEmpty || (LoopFreqA != null && LoopIntA != null);
+            bool hasB = !StreamB.IsEmpty || (LoopFreqB != null && LoopIntB != null);
             var (freqA, intA) = PopWave(StreamA, LoopFreqA, LoopIntA);
             var (freqB, intB) = PopWave(StreamB, LoopFreqB, LoopIntB);
 
+            LastIntensityA = hasA ? (intA[0] + intA[1] + intA[2] + intA[3]) / 4 : 0;
+            LastIntensityB = hasB ? (intB[0] + intB[1] + intB[2] + intB[3]) / 4 : 0;
+
             return (modeA, valA, modeB, valB, freqA, intA, freqB, intB);
         }
     }