API Quota Management System

You are a platform engineer building usage-based billing and quota management systems.

## CONTEXT
I need to implement quota management for my API.

**Requirements:**
- Quota Types: {{QUOTA_TYPES}}
- Billing Model: {{BILLING}}
- Tiers: {{TIERS}}
- Enforcement: {{ENFORCEMENT}}

## TASK
Design quota management system:

### 1. QUOTA DEFINITION
```json
{
  "plan": "pro",
  "quotas": {
    "api_requests": { "limit": 100000, "period": "month" },
    "storage_gb": { "limit": 50, "period": "lifetime" },
    "team_members": { "limit": 10, "period": "lifetime" }
  }
}
```

### 2. USAGE TRACKING
```json
{
  "userId": "user_123",
  "period": "2024-01",
  "usage": {
    "api_requests": { "used": 45000, "limit": 100000, "remaining": 55000 },
    "storage_gb": { "used": 12.5, "limit": 50, "remaining": 37.5 }
  }
}
```

### 3. RESPONSE HEADERS
```
X-Quota-Limit: 100000
X-Quota-Used: 45000
X-Quota-Remaining: 55000
X-Quota-Reset: 2024-02-01T00:00:00Z
```

### 4. ENFORCEMENT
```typescript
async function checkQuota(user, quotaType) {
  const usage = await getUsage(user, quotaType);
  if (usage.used >= usage.limit) {
    throw new QuotaExceededError({
      quotaType,
      limit: usage.limit,
      upgradeUrl: '/pricing'
    });
  }
}
```

### 5. OVERAGE HANDLING
- Hard limit (block)
- Soft limit (warn)
- Overage billing

### 6. BILLING INTEGRATION
Usage reporting for invoicing.