fix(admin-service): 修复预种价格计算公式，3566不是15831/5

totalPortionPrice 之前用 Math.floor(totalPrice/5) = 3166，但预种
价格 3566 是各权益项 floor(amount/5) 之和 + 总部吸收余额，不是
简单的整棵价格除以5。

修正为: BASE_PORTION_PRICE(3566) + floor(currentSupplement/5)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/services/admin-service/src/pricing/tree-pricing.service.ts

@@ -52,12 +52,15 @@ export class TreePricingService {
     }
 
     const totalPrice = BASE_PRICE + config.currentSupplement;
+    // 预种价格 = 基础预种价(3566) + floor(加价部分/5)
+    // 注意：3566 不是 15831/5，而是各权益项 floor(amount/5) 之和 + 总部吸收余额
+    const totalPortionPrice = BASE_PORTION_PRICE + Math.floor(config.currentSupplement / 5);
     return {
       basePrice: BASE_PRICE,
       basePortionPrice: BASE_PORTION_PRICE,
       currentSupplement: config.currentSupplement,
       totalPrice,
-      totalPortionPrice: Math.floor(totalPrice / 5),
+      totalPortionPrice,
       autoIncreaseEnabled: config.autoIncreaseEnabled,
       autoIncreaseAmount: config.autoIncreaseAmount,
       autoIncreaseIntervalDays: config.autoIncreaseIntervalDays,