feat(distribution): 分站可下调收号比例且不超过主站上限

让分销站能按自身能力下调收号比例扩大利润，同时把主站回收比例作为硬边界，避免分站把比例加得比主站更高。

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/shared/composables/usePricingCalculator.ts

@@ -19,6 +19,7 @@ import {
   hasAcceleratedSaleRatioInput as hasAcceleratedSaleRatioValue,
   isQuantityItemDisabledForInsurance,
   readFinalSaleRatio,
+  applySiteReceiveRatioDelta,
   roundMoney,
   roundRatio,
 } from '@/shared/utils/pricing'
@@ -31,6 +32,8 @@ export function usePricingCalculator(options: {
   quantityModes: Record<QuantityKey, ChargeMode>
   screenshotFiles: Record<ScreenshotKey, string[]>
   selectedSkins: Ref<string[]>
+  isDistribution?: Ref<boolean>
+  receiveRatioDelta?: Ref<number>
 }) {
   const serverOptions = computed(() => options.publishOptions.value.server_options)
   const faceOptions = computed(() => options.publishOptions.value.face_options)
@@ -85,13 +88,20 @@ export function usePricingCalculator(options: {
   const maxAcceleratedSaleRatio = computed(() =>
     calculatedDefaultSaleRatio.value > 0 ? roundRatio(calculatedDefaultSaleRatio.value + 10) : 0
   )
-  const calculatedRatio = computed(() =>
-    readFinalSaleRatio(
+  const siteReceiveRatioDelta = computed(() =>
+    Math.max(0, Number(options.receiveRatioDelta?.value || 0))
+  )
+  const calculatedRatio = computed(() => {
+    if (calculatedDefaultSaleRatio.value <= 0) return 0
+    if (options.isDistribution?.value) {
+      return applySiteReceiveRatioDelta(calculatedDefaultSaleRatio.value, siteReceiveRatioDelta.value)
+    }
+    return readFinalSaleRatio(
       calculatedDefaultSaleRatio.value,
       options.form.accelerated_sale_ratio,
       maxAcceleratedSaleRatio.value
     )
-  )
+  })
   const calculatedCoinBasePrice = computed(() => {
     if (calculatedRatio.value <= 0) return 0
     return roundMoney(coinWanAmount.value / calculatedRatio.value)
@@ -131,6 +141,9 @@ export function usePricingCalculator(options: {
   )
   const saleRatioRangeText = computed(() => {
     if (calculatedDefaultSaleRatio.value <= 0) return '完成基础信息后自动计算参考比例'
+    if (options.isDistribution?.value) {
+      return `主站上限 1:${formatNumber(calculatedDefaultSaleRatio.value)}，本站收号 1:${formatNumber(calculatedRatio.value)}`
+    }
     return `可设置 1:${formatNumber(calculatedDefaultSaleRatio.value)} ~ 1:${formatNumber(maxAcceleratedSaleRatio.value)}`
   })
   const acceleratedSaleRatioPlaceholder = computed(() => {
@@ -195,6 +208,7 @@ export function usePricingCalculator(options: {
     calculatedSellerReferenceRatio,
     calculatedDefaultSaleRatio,
     maxAcceleratedSaleRatio,
+    siteReceiveRatioDelta,
     calculatedRatio,
     calculatedCoinBasePrice,
     calculatedConsumablePrice,

frontend/src/shared/utils/pricing.ts

@@ -159,6 +159,12 @@ export function readFinalSaleRatio(
   return roundRatio(Math.min(Math.max(ratio, defaultRatio), maxAcceleratedSaleRatio))
 }
 
+export function applySiteReceiveRatioDelta(referenceRatio: number, delta: number) {
+  if (referenceRatio <= 0) return 0
+  const safeDelta = Math.min(20, Math.max(0, Number(delta) || 0))
+  return roundRatio(Math.max(referenceRatio - safeDelta, 0.01))
+}
+
 export function hasAcceleratedSaleRatioInput(value: number | '' | null | undefined) {
   const ratio = Number(value)
   return (