feat(distribution): 补齐退款加价回退、本站自卖与开通默认规则

退款时压缩卖方加价，人工/自动批次仅完结单可入账，号主收入进主站钱包；仲裁后重算释放并支持作废未入账 DS。开通时四种模式按默认生效，对外口径合并为 35/40/25，不再单独展示通道费。

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

distribution-admin/src/api.ts

@@ -115,6 +115,7 @@ export interface Site {
   display_account_enabled: boolean
   tax_enabled: boolean
   tax_rate_bps: number
+  settlement_hold_days?: number
   logo_url?: string
   favicon_url?: string
   banners_json?: string
@@ -302,9 +303,7 @@ export interface OnboardSitePayload {
   display_account_enabled?: boolean
   tax_enabled?: boolean
   tax_rate_bps?: number
-  distributor_receive_ratio?: number
-  platform_sell_ratio?: number
-  service_fee_value?: number
+  settlement_hold_days?: number
 }
 
 export interface OnboardSiteResult {
@@ -440,6 +439,11 @@ export async function settleBatch(id: number): Promise<SettlementBatch> {
   return extract(resp)
 }
 
+export async function cancelSettlementBatch(id: number): Promise<SettlementBatch> {
+  const resp = await api.post<ApiResponse<SettlementBatch>>(`/admin/distribution/settlement-batches/${id}/cancel`)
+  return extract(resp)
+}
+
 export async function listSettlementItems(batchID: number): Promise<SettlementItem[]> {
   const resp = await api.get<ApiResponse<{ items: SettlementItem[] }>>(`/admin/distribution/settlement-batches/${batchID}/items`)
   return extract(resp).items ?? []
@@ -509,6 +513,7 @@ export interface SiteWallet {
   pending_release_cent: number
   total_settled_cent: number
   total_withdrawn_cent: number
+  settlement_hold_days?: number
 }
 
 export async function fetchSiteWallet(siteID: number): Promise<SiteWallet> {