CRITICAL FIX: Add transaction confirmation to detect failed orders

- Added getConnection() method to DriftService
- Added proper transaction confirmation in openPosition()
- Check confirmation.value.err to detect on-chain failures
- Return error if transaction fails instead of assuming success
- Prevents phantom trades that never actually execute

This fixes the issue where bot was recording trades with transaction
signatures that don't exist on-chain (like 2gqrPxnvGzdRp56...).

.env

@@ -351,4 +351,5 @@ NEW_RELIC_LICENSE_KEY=
 
 USE_TRAILING_STOP=true
 TRAILING_STOP_PERCENT=0.3
-TRAILING_STOP_ACTIVATION=0.5
+TRAILING_STOP_ACTIVATION=0.5
+MIN_QUALITY_SCORE=40