feat(admin+api+player): 优胜赛结算态、禁止新增单场与钱包流水展示优化

- API/管理端：优胜赛 SETTLED 后禁止新增单场，列表与子页展示结算状态
- 玩家端：已结算 outright 只读展示并高亮冠军
- 管理端：结算后 stale 标记驱动列表刷新；财务流水时间与备注 i18n 优化
- shared：txDisplayAmount 与 LEAGUE_OUTRIGHT_SETTLED 错误码

apps/admin/src/utils/format-datetime.ts

@@ -0,0 +1,39 @@
+import { getAdminLocale } from '../i18n';
+import type { AdminLocale } from '../i18n/admin-messages';
+
+function resolveLocale(locale?: AdminLocale): AdminLocale {
+  return locale ?? getAdminLocale();
+}
+
+/** 列表展示：年月日 */
+export function formatAdminDateTimeBrief(
+  value: string | null | undefined,
+  locale?: AdminLocale,
+): string {
+  if (!value) return '—';
+  const d = new Date(value);
+  if (Number.isNaN(d.getTime())) return '—';
+  return d.toLocaleString(resolveLocale(locale), {
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+  });
+}
+
+/** 悬停详情：含秒 */
+export function formatAdminDateTimeFull(
+  value: string | null | undefined,
+  locale?: AdminLocale,
+): string {
+  if (!value) return '—';
+  const d = new Date(value);
+  if (Number.isNaN(d.getTime())) return '—';
+  return d.toLocaleString(resolveLocale(locale), {
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+    hour: '2-digit',
+    minute: '2-digit',
+    second: '2-digit',
+  });
+}