fix: adaptive price precision for meme coins

- Add adaptivePriceRound() in store/position.go for database storage
- Update position_builder.go to use adaptive precision for entry/exit prices
- Add Gate to OrderSync skip list in auto_trader.go
- Add debug logging in gate/order_sync.go for price parsing issues
- Create web/src/utils/format.ts with formatPrice() for frontend display
- Update TraderDashboardPage.tsx and PositionHistory.tsx to use adaptive formatting

Fixes issue where meme coin prices (e.g. 0.000000166) displayed as 0.0000

store/position.go

@@ -3,12 +3,63 @@ package store
 import (
 	"fmt"
 	"math"
+	"strconv"
 	"strings"
 	"time"
 
 	"gorm.io/gorm"
 )
 
+// adaptivePriceRound rounds a price based on its magnitude to preserve meaningful precision.
+// For small prices (like meme coins), it preserves more decimal places.
+// It detects the number of decimal places needed from the reference price(s).
+func adaptivePriceRound(price float64, referencePrices ...float64) float64 {
+	if price == 0 {
+		return 0
+	}
+
+	// Find the minimum magnitude among all prices (including the price itself)
+	minMagnitude := math.Abs(price)
+	for _, ref := range referencePrices {
+		if ref > 0 && ref < minMagnitude {
+			minMagnitude = ref
+		}
+	}
+
+	// Determine decimal places needed based on price magnitude
+	// For price 0.000000541, we need ~15 decimal places
+	// For price 0.0001, we need ~8 decimal places
+	// For price 1.0, we need ~4 decimal places
+	var multiplier float64
+	switch {
+	case minMagnitude < 0.000001: // Ultra small (meme coins like CHEEMS, SHIB)
+		multiplier = 1e15 // 15 decimal places
+	case minMagnitude < 0.0001: // Very small (PEPE, FLOKI)
+		multiplier = 1e12 // 12 decimal places
+	case minMagnitude < 0.01: // Small
+		multiplier = 1e10 // 10 decimal places
+	case minMagnitude < 1: // Medium
+		multiplier = 1e8 // 8 decimal places
+	default: // Large
+		multiplier = 1e6 // 6 decimal places
+	}
+
+	return math.Round(price*multiplier) / multiplier
+}
+
+// getPriceDecimalPlaces returns the number of decimal places in a price string
+func getPriceDecimalPlaces(price float64) int {
+	if price == 0 {
+		return 0
+	}
+	s := strconv.FormatFloat(price, 'f', -1, 64)
+	idx := strings.Index(s, ".")
+	if idx == -1 {
+		return 0
+	}
+	return len(s) - idx - 1
+}
+
 // TraderStats trading statistics metrics
 type TraderStats struct {
 	TotalTrades    int     `json:"total_trades"`
@@ -156,8 +207,8 @@ func (s *PositionStore) UpdatePositionQuantityAndPrice(id int64, addQty float64,
 	newQty := math.Round((pos.Quantity+addQty)*10000) / 10000
 	newEntryQty := math.Round((currentEntryQty+addQty)*10000) / 10000
 	newEntryPrice := (pos.EntryPrice*pos.Quantity + addPrice*addQty) / newQty
-	// Use 8 decimal places for price precision (crypto standard)
-	newEntryPrice = math.Round(newEntryPrice*100000000) / 100000000
+	// Use adaptive precision based on price magnitude (for meme coins with very small prices)
+	newEntryPrice = adaptivePriceRound(newEntryPrice, pos.EntryPrice, addPrice)
 	newFee := pos.Fee + addFee
 	nowMs := time.Now().UTC().UnixMilli()
 
@@ -188,8 +239,8 @@ func (s *PositionStore) ReducePositionQuantity(id int64, reduceQty float64, exit
 	var newExitPrice float64
 	if newClosedQty > 0 {
 		newExitPrice = (pos.ExitPrice*closedQty + exitPrice*reduceQty) / newClosedQty
-		// Use 8 decimal places for price precision (crypto standard)
-		newExitPrice = math.Round(newExitPrice*100000000) / 100000000
+		// Use adaptive precision based on price magnitude (for meme coins with very small prices)
+		newExitPrice = adaptivePriceRound(newExitPrice, pos.ExitPrice, exitPrice, pos.EntryPrice)
 	}
 
 	nowMs := time.Now().UTC().UnixMilli()

store/position_builder.go

@@ -147,8 +147,8 @@ func (pb *PositionBuilder) handleClose(
 		var finalExitPrice float64
 		if totalClosed > 0 {
 			finalExitPrice = (position.ExitPrice*closedBefore + price*closeQty) / totalClosed
-			// Use 8 decimal places for price precision (crypto standard)
-			finalExitPrice = math.Round(finalExitPrice*100000000) / 100000000
+			// Use adaptive precision based on price magnitude (for meme coins with very small prices)
+			finalExitPrice = adaptivePriceRound(finalExitPrice, position.ExitPrice, price, position.EntryPrice)
 		} else {
 			finalExitPrice = price
 		}