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/legacy/models/publish_task.py

@@ -0,0 +1,34 @@
+"""发布任务：一次 ImportProductsV3 请求与轮询结果。"""
+# ⚠️ 冻结代码（Ozon API 直传链路）：保留不维护，V2.1 起接口保留但不再投入。
+from __future__ import annotations
+
+import uuid
+from datetime import datetime
+
+from sqlalchemy import BigInteger, DateTime, Enum, ForeignKey, Uuid, func
+from sqlalchemy.orm import Mapped, mapped_column
+
+from db import Base
+from models.enums import PublishStatus
+from models.types import JSONType
+
+
+class PublishTask(Base):
+    __tablename__ = "publish_tasks"
+
+    id: Mapped[uuid.UUID] = mapped_column(Uuid(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    product_id: Mapped[uuid.UUID] = mapped_column(
+        Uuid(as_uuid=True), ForeignKey("products.id", ondelete="CASCADE"), index=True
+    )
+    shop_id: Mapped[uuid.UUID] = mapped_column(
+        Uuid(as_uuid=True), ForeignKey("shops.id", ondelete="CASCADE"), index=True
+    )
+    ozon_task_id: Mapped[int | None] = mapped_column(BigInteger, nullable=True, index=True)
+    status: Mapped[PublishStatus] = mapped_column(
+        Enum(PublishStatus, native_enum=False, length=16), default=PublishStatus.pending, index=True
+    )
+    request_payload: Mapped[dict | None] = mapped_column(JSONType, nullable=True)  # 脱敏后的 items[0]
+    response: Mapped[dict | None] = mapped_column(JSONType, nullable=True)         # import/info 原始结果
+    errors: Mapped[list | None] = mapped_column(JSONType, nullable=True)
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
+    completed_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)