Initial implementation of HeisserDraht buzz wire game

ESP32-C3 based hot wire game with WS2812B LED effects,
SSD1306 OLED display, debounced touch detection, and
full game state machine (IDLE → COUNTDOWN → PLAYING → GAME_OVER).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

game_logic.h

@@ -0,0 +1,37 @@
+#ifndef GAME_LOGIC_H
+#define GAME_LOGIC_H
+
+#include <Arduino.h>
+
+// Game states
+enum GameState {
+  STATE_IDLE,
+  STATE_COUNTDOWN,
+  STATE_PLAYING,
+  STATE_GAME_OVER
+};
+
+// Game data
+struct GameData {
+  GameState state;
+  uint8_t   strikes;
+  int       score;
+  unsigned long gameStartMs;
+  unsigned long elapsedMs;
+  uint8_t   countdownValue;    // 3, 2, 1, 0(GO!)
+  unsigned long countdownStepMs;
+  bool      touchActive;       // true while wire is being touched
+  unsigned long lastTouchMs;
+  unsigned long lastButtonMs;
+  bool      won;               // true if timer ran out with strikes < MAX
+};
+
+void gameInit();
+void gameUpdate();
+GameData& gameGetData();
+
+// Called by main loop to check inputs
+void gameCheckStartButton();
+void gameCheckTouch();
+
+#endif // GAME_LOGIC_H