Move Swap to connect row, show limiter values, fix trackbar keys

- Swap checkbox moved up to the Connect/device line
- Limiter values shown as separate labels (plain, 32px wide for 3 digits)
- Trackbar keyboard: Up/PageUp/Home = increase, Down/PageDown/End = decrease
- Fix Lim B trackbar clipping (moved down to avoid overlap with Lim A)

State.cs

@@ -25,6 +25,7 @@ public class State
     public int MaxB = 200;
     public LimitMode LimitModeA = LimitMode.Clamp;
     public LimitMode LimitModeB = LimitMode.Clamp;
+    public bool SwapChannels;
 
     public void SetLimitA(int max, LimitMode mode)
     {
@@ -129,6 +130,19 @@ public class State
             LastIntensityA = hasA ? (intA[0] + intA[1] + intA[2] + intA[3]) / 4 : 0;
             LastIntensityB = hasB ? (intB[0] + intB[1] + intB[2] + intB[3]) / 4 : 0;
 
+            if (SwapChannels)
+            {
+                (valA, valB) = (valB, valA);
+                (modeA, modeB) = (modeB, modeA);
+                (freqA, freqB) = (freqB, freqA);
+                (intA, intB) = (intB, intA);
+                (LastSentA, LastSentB) = (LastSentB, LastSentA);
+                (LastFreqA, LastFreqB) = (LastFreqB, LastFreqA);
+                (LastIntA, LastIntB) = (LastIntB, LastIntA);
+                (LastActiveA, LastActiveB) = (LastActiveB, LastActiveA);
+                (LastIntensityA, LastIntensityB) = (LastIntensityB, LastIntensityA);
+            }
+
             return (modeA, valA, modeB, valB, freqA, intA, freqB, intB);
         }
     }