=== Phase 4 Billing Integration Validation ===

Test 1: Constructor validation
  Parameters count: 4
  Expected: 4
  ✓ Constructor has correct parameter count
  Parameters:
    - $textSender: BuyerKiosk\SMS\TextMessageService\TextSenderInterface
    - $store: mixed
    - $storeDB: mixed
    - $usageTracker: BuyerKiosk\Billing\Services\SmsUsageTrackerInterface

Test 2: Store creates usage tracker
  ✓ createSmsUsageTracker returns SmsUsageTrackerInterface
  Tracker class: BuyerKiosk\Billing\Services\SmsUsageTracker

Test 3: NullTracker compatibility
  ✓ TextMessageService created with NullSmsUsageTracker

Test 4: Segment count calculation
  ✓ calculateSegmentCount correctly counts 160 chars as 1 segment
  ✗ FAIL: Expected 2 segments for emoji, got 3