Implement core hostile NPC combat system infrastructure:
- Add #hostile tag handler to chat-helpers.js for Ink integration
- Fix security-guard.ink to use proper hub pattern with -> hub instead of -> END
- Add #hostile:security_guard tags to hostile conversation paths
- Create combat configuration system (combat-config.js)
- Create combat event constants (combat-events.js)
- Implement player health tracking system with HP and KO state
- Implement NPC hostile state management with HP tracking
- Add combat debug utilities for testing
- Add error handling utilities for validation
- Integrate combat systems into game.js create() method
- Create test-hostile.ink for testing hostile tag system
This establishes the foundation for hostile NPC behavior, allowing NPCs to
become hostile through Ink dialogue and tracking health for both player and NPCs.
