- Fix PriceLevels field access (use private field priceLevels)
- Add missing math import in orderbook_extended.go
- Remove unused log import from websocket_server.go
- Fix MarginEngine method calls (use CheckLiquidations instead of GetAllPositions)
- Fix SimpleVault active status check (use member count instead)
- Fix ClearingHouse field name (clearinghouse not clearingHouse)
- Comment out incomplete orderBook integration in vault_simple.go
- Fix broadcast channel type mismatch (convert Message to []byte)