Update logic to avoid collision

Co-authored-by: Copilot <copilot@github.com>

src/ButtonEventManager.h

@@ -26,8 +26,6 @@ class ButtonEventManager {
  public:
   using Button = MappedInputManager::Button;
 
-  static constexpr int NUM_BUTTONS = 9;  // matches MappedInputManager::Button count
-
   enum class PressType { Short, Double, Long };
 
   struct ButtonEvent {
@@ -56,9 +54,13 @@ class ButtonEventManager {
   static bool hasDoubleAction(Button button);
 
  private:
+  // Up and Down alias the same physical GPIO pins as PageBack/PageForward (via sideButtonLayout).
+  // Running separate FSMs for both would double-fire on every side button press.
+  // Up/Down are therefore excluded here; their configurable actions are resolved in main.cpp
+  // by treating a PageBack/PageForward event as the canonical side-button event.
+  static constexpr int NUM_BUTTONS = 7;
   static constexpr Button ALL_BUTTONS[NUM_BUTTONS] = {
-      Button::Back, Button::Confirm,  Button::Left,        Button::Right, Button::Up,
-      Button::Down, Button::PageBack, Button::PageForward, Button::Power,
+      Button::Back, Button::Confirm, Button::Left, Button::Right, Button::PageBack, Button::PageForward, Button::Power,
   };
 
   enum class State { Idle, Pressed, ReleasedOnce, DoublePressed };