feat: add accessory models and box_item item_type column

Add FinishedGoodsAccessory and AccessoryType ORM models for the
accessory module. Add item_type column to FinishedGoodsBoxItem to
distinguish between products and accessories in boxing records.

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

app/models/accessory.py

@@ -0,0 +1,44 @@
+# app/models/accessory.py
+from datetime import datetime
+
+from sqlalchemy import BigInteger, DateTime, Index, Integer, String, func
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.database import Base
+
+SCHEMA = "CargoTrace"
+
+
+class FinishedGoodsAccessory(Base):
+    __tablename__ = "finished_goods_accessory"
+    __table_args__ = (
+        Index("idx_fga_paichan_no", "paichan_no"),
+        Index("idx_fga_zongpai_no", "zongpai_no"),
+        Index("idx_fga_location_code", "location_code"),
+        {"schema": SCHEMA},
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    paichan_no: Mapped[str] = mapped_column(String(64), nullable=False)
+    zongpai_no: Mapped[str] = mapped_column(String(64), nullable=False)
+    accessory_type: Mapped[str] = mapped_column(String(64), nullable=False)
+    quantity: Mapped[int] = mapped_column(Integer, nullable=False)
+    location_code: Mapped[str | None] = mapped_column(String(64), nullable=True)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime,
+        nullable=False,
+        default=func.current_timestamp(),
+        server_default=func.current_timestamp(),
+    )
+
+
+class AccessoryType(Base):
+    __tablename__ = "accessory_type"
+    __table_args__ = (
+        Index("uk_accessory_type_name", "name", unique=True),
+        {"schema": SCHEMA},
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    name: Mapped[str] = mapped_column(String(64), nullable=False)
+    sort_order: Mapped[int] = mapped_column(Integer, nullable=False, default=0)

app/models/finished_goods.py

@@ -58,6 +58,9 @@ class FinishedGoodsBoxItem(Base):
     box_id: Mapped[int] = mapped_column(BigInteger, nullable=False)
     zongpai_no: Mapped[str] = mapped_column(String(64), nullable=False)
     quantity: Mapped[float | None] = mapped_column(Numeric(18, 3), nullable=True)
+    item_type: Mapped[str] = mapped_column(
+        String(16), nullable=False, default="product", server_default="product"
+    )
     created_at: Mapped[datetime] = mapped_column(
         DateTime,
         nullable=False,