Listing模块：完成分字段重构

核心改造：
1. ListingDTO改为使用PriceCent和DepositAmountCent字段
2. toDTO函数使用listing.PriceCent和listing.DepositAmountCent
3. 筛选函数matchPublicQuery转换为元进行比较
4. 排序函数sortPublicListings使用PriceCent比较
5. 价格视图函数sanitizePriceForOwner使用PriceCent
6. toAdminDTO函数使用*Cent字段

技术细节：
- 筛选时将分转为元：price := float64(item.PriceCent) / 100
- 排序直接比较分：a.PriceCent < b.PriceCent
- 价格调整时转换：item.PriceCent = int64(math.Round(sellerPrice * 100))
- 编译验证通过 ✅

backend/internal/modules/listing/dto.go

@@ -25,8 +25,8 @@ type ListingDTO struct {
 	AssetSummary   map[string]any `json:"asset_summary,omitempty"`
 	ScreenshotURLS []string       `json:"screenshot_urls"`
 	CoverURL       string         `json:"cover_url"`
-	Price          float64        `json:"price"`
-	DepositAmount  float64        `json:"deposit_amount"`
+	PriceCent      int64          `json:"price_cent"`
+	DepositAmountCent int64       `json:"deposit_amount_cent"`
 	IsAccelerated  bool           `json:"is_accelerated_sale"`
 	InTransaction  bool           `json:"in_transaction"`
 	Status         string         `json:"status"`

backend/internal/modules/listing/repository.go

@@ -908,8 +908,8 @@ func matchesPublicQuery(item ListingDTO, query PublicListQuery) bool {
 		return false
 	}
 
-	price := item.Price
-	deposit := item.DepositAmount
+	price := float64(item.PriceCent) / 100
+	deposit := float64(item.DepositAmountCent) / 100
 	total := price + deposit
 	coinM := coinMFromListing(item)
 	if !numberInRange(coinM, NumberRange{Min: query.MinCoin, Max: query.MaxCoin}) {
@@ -944,9 +944,9 @@ func sortPublicListings(items []ListingDTO, sortKey string) {
 		b := items[j]
 		switch sortKey {
 		case "priceAsc":
-			return a.Price < b.Price
+			return a.PriceCent < b.PriceCent
 		case "priceDesc":
-			return a.Price > b.Price
+			return a.PriceCent > b.PriceCent
 		case "coinDesc":
 			return a.HafCoinAmount > b.HafCoinAmount
 		case "awmDesc":
@@ -1421,7 +1421,7 @@ func applySellerListingPrice(item *ListingDTO) {
 	}
 	sellerPrice := readSummaryNumber(breakdown["seller_total_price"])
 	if sellerPrice > 0 {
-		item.Price = sellerPrice
+		item.PriceCent = int64(math.Round(sellerPrice * 100))
 	}
 	sellerRatio := readSummaryNumber(breakdown["seller_ratio"])
 	if sellerRatio > 0 {
@@ -1455,8 +1455,8 @@ func (row listingRow) toDTO() ListingDTO {
 		AssetSummary:      assetSummary,
 		ScreenshotURLS:    screenshotURLS,
 		CoverURL:          publicCoverURL(row.ID, screenshotURLS, row.Status, row.ReviewStatus),
-		Price:          row.Price,
-		DepositAmount:  row.DepositAmount,
+		PriceCent:         row.PriceCent,
+		DepositAmountCent: row.DepositAmountCent,
 		IsAccelerated:     isAcceleratedSale(assetSummary),
 		InTransaction:     row.InTransaction,
 		Status:            row.Status,
@@ -1487,8 +1487,8 @@ func toDTO(account model.GameAccount, listing model.RentalListing) *ListingDTO {
 		AssetSummary:      assetSummary,
 		ScreenshotURLS:    screenshotURLS,
 		CoverURL:          publicCoverURL(listing.ID, screenshotURLS, listing.Status, listing.ReviewStatus),
-		Price:          listing.Price,
-		DepositAmount:  listing.DepositAmount,
+		PriceCent:         listing.PriceCent,
+		DepositAmountCent: listing.DepositAmountCent,
 		IsAccelerated:     isAcceleratedSale(assetSummary),
 		InTransaction:     listing.InTransaction,
 		Status:            listing.Status,