feat(models): 期1 模特库地基 — Model 顶级实体 + 模特库页 + 审核范围扩展

后端:
- 新增 Model(模特)团队级实体:形象图+三视图+声线(声线尾期),官方模板标签,软删
- Asset.Category 枚举一次加全(model_portrait/tri_view/voice/model_tryon/platform_kit/free_create/storyboard),逐期接线
- 送审范围 person → REVIEW_CATEGORIES{person,tri_view,storyboard}(review.py + adminpanel 队列),图片趴不送审;当前行为不变(forward-compat)
- /api/models/ ModelLibraryViewSet:本团队∪官方模板、官方/我的 tab、真人上传、软删(官方不可删)、跨团队资产引用防越权
- backfill_models 命令把历史成套模特(kind=model + 项目流命名配对)归集成 Model,dry-run 默认

前端:
- 左菜单新增「模特库」顶级入口(person 图标)+ 路由 /models
- 模特库页:全部/官方模板/我的模特 tab + 真人上传 + 模特卡(形象图+三视图缩略+官方标签),仅用 design token

测试:assets 10/10 绿;tsc+build 全绿;无头走查 0 console error(全部5/官方3/我的2,官方标签达标)
基线既有 7 失败(ai/projects provider mock 漂移)零新增

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/frontend/src/App.tsx

@@ -41,6 +41,7 @@ import type { AuthMode, NavigateOptions, Notice, Page, ResolvedRoute } from "./r
 import { pathForPage, resolveRoute, routeLabels } from "./routes/route-config";
 import { AdminApp } from "./routes/admin/admin-app";
 import { TrashPage } from "./routes/trash";
+import { ModelsPage } from "./routes/models";
 import { money } from "./routes/stage-config";
 
 const crumbLabels: Partial<Record<Page, string>> = {
@@ -743,6 +744,8 @@ export function App() {
             </div>
           </div>
         );
+      case "models":
+        return <ModelsPage />;
       case "library":
         return <LibraryPage onUpload={(formData) => action(() => api.uploadAsset(formData), "资产已上传")} onDelete={(id) => action(() => api.deleteAsset(id), "资产已删除")} />;
       case "trash":