Add intro scene with title screen

- Create IntroScene with ocean-themed background
- Display game title and 18th century whaling subtitle
- Add decorative waves and ship silhouette
- Implement START GAME button with hover effects
- Initialize inventory and transition to ShipDeckScene

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/main.js

@@ -1,4 +1,5 @@
 import Phaser from 'phaser';
+import IntroScene from './scenes/IntroScene.js';
 import ShipDeckScene from './scenes/ShipDeckScene.js';
 import MapScene from './scenes/MapScene.js';
 import TransitionScene from './scenes/TransitionScene.js';
@@ -10,7 +11,7 @@ const config = {
     height: 600,
     parent: 'game-container',
     backgroundColor: '#2d5f8e',
-    scene: [ShipDeckScene, MapScene, TransitionScene, HuntingScene],
+    scene: [IntroScene, ShipDeckScene, MapScene, TransitionScene, HuntingScene],
     physics: {
         default: 'arcade',
         arcade: {