refactor(server): 移除鉴权并归档遗留路由至 legacy/

- 删除 auth.py 与 deps.py，各路由去除 get_current_user 依赖
- collection.py 更名为 materials.py，冻结链路（ozon/publish/shops/categories）移入 legacy/
- 扩展默认生图服务端口并入 8800 并自动迁移旧配置，水印默认文案改为 Panda Store
- 新增 docs/v2.1/backend-structure.md 后端结构盘点文档

server/main.py

@@ -5,7 +5,7 @@ from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
 from sqlalchemy import text
 
-from api import ai, auth, categories, collection, export, fx, image, ozon, products, proxy, publish, shops, suite
+from api import ai, export, fx, image, materials, products, proxy, suite
 from config import get_settings
 from db import get_engine
 
@@ -26,22 +26,25 @@ if settings.cors_origin_list:
         allow_headers=["*"],
     )
 
-# 业务路由
-app.include_router(auth.router)
-app.include_router(collection.router)
+# 业务路由（活跃：采集上报 / 商品库 / 套图生图 / 辅助）
+app.include_router(materials.router)
 app.include_router(products.router)
-app.include_router(shops.router)
-app.include_router(categories.router)
-app.include_router(publish.router)
 app.include_router(fx.router)
 app.include_router(ai.router)
 app.include_router(image.router)
-app.include_router(ozon.router)
 # V2.1 套图生图（试算页 04 区块）/ 导出 / 图片代理
 app.include_router(suite.router)
 app.include_router(export.router)
 app.include_router(proxy.router)
 
+# ⚠️ 冻结链路（Ozon API 直传）：代码移至 legacy/，接口保留但不再投入
+from legacy.api import categories, ozon, publish, shops  # noqa: E402
+
+app.include_router(shops.router)
+app.include_router(categories.router)
+app.include_router(publish.router)
+app.include_router(ozon.router)
+
 
 @app.on_event("startup")
 async def on_startup() -> None: