- Created SoundManager class for handling audio playback using Phaser's sound system.
- Added methods for preloading, initializing, and playing sounds with volume control.
- Integrated UI sound helpers for easier sound attachment to DOM elements.
- Updated game.js to initialize sound manager and preload sounds.
- Modified interactions.js, unlock-system.js, and panels.js to play appropriate sounds on interactions.
- Created SOUND_SYSTEM_QUICK_REFERENCE.md for documentation on sound system usage.
- Optimized NPCBarkSystem and NPCManager with caching and event listener cleanup.
