Add trailing stop feature for runner position + fix settings persistence

- Implemented trailing stop logic in Position Manager for remaining position after TP2
- Added new ActiveTrade fields: tp2Hit, trailingStopActive, peakPrice
- New config settings: useTrailingStop, trailingStopPercent, trailingStopActivation
- Added trailing stop UI section in settings page with explanations
- Fixed env file parsing regex to support numbers in variable names (A-Z0-9_)
- Settings now persist correctly across container restarts
- Added back arrow navigation on settings page
- Updated all API endpoints and test files with new fields
- Trailing stop activates when runner reaches configured profit level
- SL trails below peak price by configurable percentage

app/api/trading/execute/route.ts

@@ -198,11 +198,14 @@ export async function POST(request: NextRequest): Promise<NextResponse<ExecuteTr
       emergencyStopPrice,
       currentSize: positionSizeUSD,
       tp1Hit: false,
+      tp2Hit: false,
       slMovedToBreakeven: false,
       slMovedToProfit: false,
+      trailingStopActive: false,
       realizedPnL: 0,
       unrealizedPnL: 0,
       peakPnL: 0,
+      peakPrice: entryPrice,
       priceCheckCount: 0,
       lastPrice: entryPrice,
       lastUpdateTime: Date.now(),