- Updated AccountBalance interface to include netUsdValue and unrealizedPnl
- Enhanced getAccountBalance() to calculate Net USD Value (collateral + unrealized PnL)
- Added Net USD Value calculation from all position unrealized PnL
- Updated Dashboard.tsx to display Net USD Value as primary metric
- Added new stats card with emerald styling for Net USD Value
- Reorganized stats grid to 6 columns to accommodate new metric
- Net USD Value = Total Collateral + Total Unrealized PnL from all positions