fix(抽奖): 概率按 weight/1000 显示与录入（支持小数%，总权重100000=100%）

- prize-grid: 概率预览/合计/卡片改用 weightToPercent(weight/1000)，
  合计校验对齐 FULL_TOTAL_WEIGHT=100000；修正原来把原始 weight 当 % 显示（如 49901%）
- prize-form: 概率输入按百分比(0-100，step 0.001)，提交 ×1000 存 weight，回填 ÷1000

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/admin/src/sections/lottery/prize-form.tsx

@@ -43,6 +43,8 @@ import { toast } from "sonner";
 import { z } from "zod";
 
 const CENTS_PER_YUAN = 100;
+// 概率单位约定：weight 1000 = 1%（支持 3 位小数概率，总权重 100000 = 100%）。
+const WEIGHT_PER_PERCENT = 1000;
 
 type TranslateFn = (key: string, defaultValue: string) => string;
 
@@ -102,7 +104,6 @@ const getPrizeSchema = (t: TranslateFn) =>
         .optional(),
       weight: z
         .number()
-        .int(t("prize.weightInteger", "Probability must be an integer"))
         .min(0, t("prize.weightMin", "Probability must be at least 0"))
         .max(100, t("prize.weightMax", "Probability cannot exceed 100")),
       unlimited_stock: z.boolean(),
@@ -221,7 +222,7 @@ function toFormValues(prize?: API.LotteryPrize): PrizeFormValues {
     type: (prize?.type as PrizeFormValues["type"]) ?? "vpn_duration",
     name: prize?.name ?? "",
     icon_url: prize?.icon_url ?? "",
-    weight: prize?.weight ?? 1,
+    weight: (prize?.weight ?? 0) / WEIGHT_PER_PERCENT,
     unlimited_stock: prize ? prize.total_stock === null : true,
     total_stock: prize?.total_stock ?? undefined,
     is_fallback: prize?.is_fallback ?? false,
@@ -325,7 +326,9 @@ export default function PrizeForm({
         name: values.name.trim(),
         icon_url: values.icon_url?.trim() ?? "",
         config: toConfig(values),
-        weight: values.is_fallback ? 0 : values.weight,
+        weight: values.is_fallback
+          ? 0
+          : Math.round(values.weight * WEIGHT_PER_PERCENT),
         total_stock: values.unlimited_stock
           ? null
           : (values.total_stock ?? null),
@@ -643,7 +646,7 @@ export default function PrizeForm({
                   type: "number",
                   min: 0,
                   max: 100,
-                  step: 1,
+                  step: 0.001,
                   suffix: "%",
                   disabled: isFallback,
                 },