input_interpreter: Add method to check for a button press state

This allows to check for continuous input for the duration of a button press/hold

src/core/frontend/input_interpreter.h

@@ -66,6 +66,27 @@ public:
     /// Gets a button state from HID and inserts it into the array of button states.
     void PollInput();
 
+    /**
+     * Checks whether the button is pressed.
+     *
+     * @param button The button to check.
+     *
+     * @returns True when the button is pressed.
+     */
+    [[nodiscard]] bool IsButtonPressed(HIDButton button) const;
+
+    /**
+     * Checks whether any of the buttons in the parameter list is pressed.
+     *
+     * @tparam HIDButton The buttons to check.
+     *
+     * @returns True when at least one of the buttons is pressed.
+     */
+    template <HIDButton... T>
+    [[nodiscard]] bool IsAnyButtonPressed() {
+        return (IsButtonPressed(T) || ...);
+    }
+
     /**
      * The specified button is considered to be pressed once
      * if it is currently pressed and not pressed previously.