feat(api): public good detail family block behind gray-release flag

apps/api/src/public/public.service.ts

@@ -32,6 +32,16 @@ const PUBLIC_GOOD_INCLUDE = {
     include: {
       detail: true,
       variants: { orderBy: [{ sortOrder: 'asc' as const }, { id: 'asc' as const }] },
+      family: {
+        select: {
+          id: true,
+          familyCode: true,
+          familyName: true,
+          sizeChart: true,
+          packageSpecs: true,
+          priceMatrix: true,
+        },
+      },
     },
   },
   mergedOriginGoods: {
@@ -402,6 +412,42 @@ export class PublicService {
         sortOrder: variant.sortOrder,
       })),
       detailSyncedAt: detail?.syncedAt.toISOString() ?? null,
+      ...this.familyBlock(good),
+    };
+  }
+
+  /**
+   * 灰度族块（设计 D4：零新增公开端点）：仅当 PUBLIC_DETAIL_FROM_FAMILY=true
+   * 且主链接有所属族时输出；数据全部来自 ProductFamily 的物化 JSON，无额外查询。
+   */
+  private familyBlock(
+    good: PublicGoodRow,
+  ): Pick<PublicGoodDetailDto, 'family'> | Record<string, never> {
+    if (process.env.PUBLIC_DETAIL_FROM_FAMILY !== 'true') return {};
+    const family = good.originGood.family;
+    if (!family || !family.priceMatrix) return {};
+    const matrix = family.priceMatrix as {
+      sizes: Array<{ key: string; name: string | null }>;
+      colors: Array<{ key: string; name: string | null; hex: string | null; imageUrl: string | null }>;
+      crafts: string[];
+      logistics: string[];
+      rows: Array<{ price: string }>;
+    };
+    const prices = matrix.rows.map((r) => Number(r.price)).filter((n) => Number.isFinite(n));
+    return {
+      family: {
+        familyId: family.id.toString(),
+        familyCode: family.familyCode,
+        familyName: family.familyName,
+        sizes: matrix.sizes,
+        colors: matrix.colors,
+        crafts: matrix.crafts,
+        logistics: matrix.logistics,
+        sizeChart: (family.sizeChart as Record<string, unknown> | null) ?? null,
+        packageSpecs: (family.packageSpecs as Record<string, unknown> | null) ?? null,
+        priceMatrix: matrix as unknown as Record<string, unknown>,
+        minPrice: prices.length ? String(Math.min(...prices)) : null,
+      },
     };
   }