Reduce whale swimming speed

- Horizontal swim speed: 0.5-1.0 → 0.2-0.5 (60% slower)
- Vertical drift: 0.3 → 0.15 (50% slower)
- Makes whales easier to track and hit
- Better difficulty balance

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

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

src/scenes/HuntingScene.js

@@ -284,8 +284,8 @@ export default class HuntingScene extends Phaser.Scene {
         whale.setData('bobTime', 0); // Timer for bobbing animation
 
         // Swimming movement
-        whale.setData('swimSpeedX', direction * (0.5 + Math.random() * 0.5)); // 0.5-1.0 speed
-        whale.setData('swimSpeedY', (Math.random() - 0.5) * 0.3); // Slight vertical drift
+        whale.setData('swimSpeedX', direction * (0.2 + Math.random() * 0.3)); // 0.2-0.5 speed
+        whale.setData('swimSpeedY', (Math.random() - 0.5) * 0.15); // Slight vertical drift
 
         // Diving mechanics
         whale.setData('diving', false);