Function useCombatTimer

useCombatTimer(config: UseCombatTimerConfig): UseCombatTimerReturn
useCombatTimer Hook

Manages combat round countdown timer with pause support and audio warnings.

Features:
- Counts down from initial time to 0
- Pauses/resumes based on isPaused prop
- Plays audio warning at warning threshold (default 10s)
- Plays urgent audio warning at urgent threshold (default 5s)
- Calls onTimeUp when timer reaches 0
- Provides formatted time string (MM:SS)
- Returns current warning level for UI styling
Korean: 전투 라운드 타이머 관리 훅
Parameters
- config: UseCombatTimerConfig
Returns UseCombatTimerReturn
Example
```
const { timeRemaining, warningLevel, formattedTime } = useCombatTimer({
  initialTime: 180, // 3 minutes
  isPaused: false,
  onTimeUp: () => handleRoundEnd(),
  warningThreshold: 10,
  urgentThreshold: 5,
});
```
- Defined in hooks/useCombatTimer.ts:113