fix Gutte in Decrease-Mode

src/Koogle.Web/Components/Game/GameInputPanel.razor

@@ -280,7 +280,15 @@
     private async Task HandleGutterClick(bool isLeft)
     {
         // Gutter = 0 pins fallen, auto-confirm throw
-        Dispatcher.Dispatch(new ResetPinsAction());
+        // In Decrease mode, preserve disabled pins (already knocked down)
+        if (GameState.Value.ThrowPanelAfter.ThrowMode == ThrowMode.Decrease)
+        {
+            Dispatcher.Dispatch(new ClearFallenPinsAction());
+        }
+        else
+        {
+            Dispatcher.Dispatch(new ResetPinsAction());
+        }
         _selectedNumber = 0;
 
         await ConfirmThrow(isGutter: true, isLeftGutter: isLeft);

src/Koogle.Web/Store/GameState/GameActions.cs

@@ -151,6 +151,12 @@ public record SetPinStatusAction(int PinNumber, PinStatus Status);
 /// </summary>
 public record ResetPinsAction;
 
+/// <summary>
+/// Action to clear fallen pins (set to standing) while preserving disabled pins.
+/// Used in Decrease mode for gutter throws.
+/// </summary>
+public record ClearFallenPinsAction;
+
 /// <summary>
 /// Action to set the bell value.
 /// </summary>

src/Koogle.Web/Store/GameState/GameReducers.cs

@@ -309,6 +309,16 @@ public static class GameReducers
             ThrowPanelAfter = state.ThrowPanelAfter.ResetPins()
         };
 
+    /// <summary>
+    /// Handles ClearFallenPinsAction - clears fallen pins while preserving disabled.
+    /// </summary>
+    [ReducerMethod(typeof(ClearFallenPinsAction))]
+    public static GameState OnClearFallenPins(GameState state)
+        => state with
+        {
+            ThrowPanelAfter = state.ThrowPanelAfter.ClearFallenPins()
+        };
+
     /// <summary>
     /// Handles SetBellValueAction - sets bell value.
     /// </summary>

src/Koogle.Web/Store/GameState/GameState.cs

@@ -297,6 +297,23 @@ public record ThrowPanelState
         Pin9 = Pin9 == PinStatus.Fallen ? PinStatus.Disabled : Pin9
     };
 
+    /// <summary>
+    /// Clears fallen pins (sets to standing) while preserving disabled pins.
+    /// Used for gutter throws in Decrease mode.
+    /// </summary>
+    public ThrowPanelState ClearFallenPins() => this with
+    {
+        Pin1 = Pin1 == PinStatus.Fallen ? PinStatus.Standing : Pin1,
+        Pin2 = Pin2 == PinStatus.Fallen ? PinStatus.Standing : Pin2,
+        Pin3 = Pin3 == PinStatus.Fallen ? PinStatus.Standing : Pin3,
+        Pin4 = Pin4 == PinStatus.Fallen ? PinStatus.Standing : Pin4,
+        Pin5 = Pin5 == PinStatus.Fallen ? PinStatus.Standing : Pin5,
+        Pin6 = Pin6 == PinStatus.Fallen ? PinStatus.Standing : Pin6,
+        Pin7 = Pin7 == PinStatus.Fallen ? PinStatus.Standing : Pin7,
+        Pin8 = Pin8 == PinStatus.Fallen ? PinStatus.Standing : Pin8,
+        Pin9 = Pin9 == PinStatus.Fallen ? PinStatus.Standing : Pin9
+    };
+
     /// <summary>
     /// Checks if all pins are knocked down (fallen or disabled).
     /// </summary>