fix: OKX trading issues and improve position tracking

- Add maxMktSz check for OKX market orders to prevent exceeding limits
- Increase margin safety buffer (0.1% fee + 1% buffer) for all exchanges
- Fix Binance position closure detection with direct trade queries
- Move Recent Completed Trades before Current Positions in AI prompt
- Update README screenshots with table layout for better alignment

decision/engine.go

@@ -854,17 +854,7 @@ func (e *StrategyEngine) BuildUserPrompt(ctx *Context) string {
 		ctx.Account.MarginUsedPct,
 		ctx.Account.PositionCount))
 
-	// Position information
-	if len(ctx.Positions) > 0 {
-		sb.WriteString("## Current Positions\n")
-		for i, pos := range ctx.Positions {
-			sb.WriteString(e.formatPositionInfo(i+1, pos, ctx))
-		}
-	} else {
-		sb.WriteString("Current Positions: None\n\n")
-	}
-
-	// Recently completed orders
+	// Recently completed orders (placed before positions to ensure visibility)
 	if len(ctx.RecentOrders) > 0 {
 		sb.WriteString("## Recent Completed Trades\n")
 		for i, order := range ctx.RecentOrders {
@@ -881,6 +871,16 @@ func (e *StrategyEngine) BuildUserPrompt(ctx *Context) string {
 		sb.WriteString("\n")
 	}
 
+	// Position information
+	if len(ctx.Positions) > 0 {
+		sb.WriteString("## Current Positions\n")
+		for i, pos := range ctx.Positions {
+			sb.WriteString(e.formatPositionInfo(i+1, pos, ctx))
+		}
+	} else {
+		sb.WriteString("Current Positions: None\n\n")
+	}
+
 	// Candidate coins
 	sb.WriteString(fmt.Sprintf("## Candidate Coins (%d coins)\n\n", len(ctx.MarketDataMap)))
 	displayedCount := 0