fix(distribution): 分成改为分主站提价利润，分站自主提价溢价全额归卖方

- 文档：升级至 v0.7，固化号主保底、主站提价利润分账（35/40/25）与分站加价溢价独享逻辑
- 定价：修正货架兑换比例调价方向为调减比例提价（site_ratio = base_ratio - delta）
- 分账：分成基数剔除号主成本与分站加价，提价利润按规则切分，分站自主加价溢价 100% 归卖出方
- 前端：更新分销后台提价说明文案，提示调减比例提高售价且溢价归本站

backend/internal/modules/listing/service_test.go

@@ -701,7 +701,7 @@ func TestListPublicWithDistributionSiteCode(t *testing.T) {
 	site := model.DistributionSite{SiteCode: "site_alpha", SiteName: "分销A", Domain: "a.com", Status: "active", DisplayAccountEnabled: true}
 	db.Create(&site)
 
-	dsa := model.DistributionSiteAccount{SiteID: site.ID, AccountID: account1.ID, ListingID: l1.ID, DisplayStatus: "enabled", ShelfRatioDelta: 25}
+	dsa := model.DistributionSiteAccount{SiteID: site.ID, AccountID: account1.ID, ListingID: l1.ID, DisplayStatus: "enabled", ShelfRatioDelta: 20}
 	db.Create(&dsa)
 
 	res, err := repo.ListPublic(context.Background(), PublicListQuery{
@@ -713,16 +713,17 @@ func TestListPublicWithDistributionSiteCode(t *testing.T) {
 	if len(res.Items) != 1 || res.Items[0].ListingNo != "L101" {
 		t.Fatalf("expected only L101, got %+v", res.Items)
 	}
-	if res.Items[0].PriceCent != 8000 {
-		t.Fatalf("expected public price 8000 with ratio delta, got %d", res.Items[0].PriceCent)
+	// 主站 100 元 (10000 分，100 比例)；分站提价减 20 比例 (80 比例) → 售价 125 元 (12500 分)
+	if res.Items[0].PriceCent != 12500 {
+		t.Fatalf("expected public price 12500 with ratio delta, got %d", res.Items[0].PriceCent)
 	}
 
 	detail, err := repo.FindPublic(context.Background(), l1.ID, "site_alpha")
 	if err != nil {
 		t.Fatalf("FindPublic err: %v", err)
 	}
-	if detail.PriceCent != 8000 {
-		t.Fatalf("expected detail price 8000 with ratio delta, got %d", detail.PriceCent)
+	if detail.PriceCent != 12500 {
+		t.Fatalf("expected detail price 12500 with ratio delta, got %d", detail.PriceCent)
 	}
 	mainDetail, err := repo.FindPublic(context.Background(), l1.ID, "")
 	if err != nil {

backend/internal/modules/listing/shelf_ratio.go

@@ -13,7 +13,9 @@ func BaseExchangeRatio(hafCoinAmount, priceCent int64) float64 {
 	return roundRatio(CoinWan(hafCoinAmount) / centToYuan(priceCent))
 }
 
-// ApplyShelfRatio 按分站加价比例重算售价。delta=0 时保持原价，避免四舍五入漂移。
+// ApplyShelfRatio 按分站加价比例重算售价。
+// 在「1 元兑换多少万哈夫币」的比例机制下：比例越小，售价越高（提价）；比例越大，售价越低（打折）。
+// 分站货架自主提价应调小兑换比例（siteRatio = baseRatio - ratioDelta），使分站售价高于主站基准价。
 func ApplyShelfRatio(hafCoinAmount, basePriceCent int64, ratioDelta float64) (priceCent int64, baseRatio, siteRatio float64) {
 	baseRatio = BaseExchangeRatio(hafCoinAmount, basePriceCent)
 	if ratioDelta < 0 {
@@ -22,13 +24,13 @@ func ApplyShelfRatio(hafCoinAmount, basePriceCent int64, ratioDelta float64) (pr
 	if baseRatio <= 0 || ratioDelta == 0 {
 		return basePriceCent, baseRatio, baseRatio
 	}
-	siteRatio = roundRatio(baseRatio + ratioDelta)
-	if siteRatio <= 0 {
-		return basePriceCent, baseRatio, baseRatio
+	siteRatio = roundRatio(baseRatio - ratioDelta)
+	if siteRatio <= 0.01 {
+		siteRatio = 0.01
 	}
 	priceCent = yuanToCent(CoinWan(hafCoinAmount) / siteRatio)
-	if priceCent < 0 {
-		priceCent = 0
+	if priceCent < basePriceCent {
+		priceCent = basePriceCent
 	}
 	return priceCent, baseRatio, siteRatio
 }

backend/internal/modules/listing/shelf_ratio_test.go

@@ -2,17 +2,18 @@ package listing
 
 import "testing"
 
-func TestApplyShelfRatioIncreasesExchangeRatio(t *testing.T) {
-	// 100M = 10000 万，主站 100 元 → 1 元 = 100w
-	price, base, site := ApplyShelfRatio(100_000_000, 10000, 25)
+func TestApplyShelfRatioIncreasesPriceByLoweringRatio(t *testing.T) {
+	// 100M = 10000 万，主站 100 元 → 1 元 = 100w 比例
+	// 分站提价减 20 比例 → 1 元 = 80w 比例 → 售价 125 元 (12500 分)
+	price, base, site := ApplyShelfRatio(100_000_000, 10000, 20)
 	if base != 100 {
 		t.Fatalf("base ratio = %v, want 100", base)
 	}
-	if site != 125 {
-		t.Fatalf("site ratio = %v, want 125", site)
+	if site != 80 {
+		t.Fatalf("site ratio = %v, want 80", site)
 	}
-	if price != 8000 {
-		t.Fatalf("site price = %d, want 8000", price)
+	if price != 12500 {
+		t.Fatalf("site price = %d, want 12500", price)
 	}
 }