Adding sync with imported parts

app/models/augmented_part.py

@@ -2,6 +2,8 @@ from sqlalchemy import ForeignKey, String
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
 from app.core.database import Base
+from app.models.associations import augmented_part_imported_parts
+from app.models.imported_part import ImportedPart
 from app.models.manufacturer import Manufacturer
 from app.models.part_colour import PartColour
 from app.models.part_type import PartType
@@ -31,6 +33,11 @@ class AugmentedPart(Base):
         ForeignKey("sub_part_types.id", ondelete="SET NULL"), nullable=True, default=None
     )
 
+    # linked imported parts — not eagerly loaded; used by sync service only
+    imported_parts: Mapped[list[ImportedPart]] = relationship(
+        secondary=augmented_part_imported_parts, lazy="select"
+    )
+
     colour: Mapped[PartColour] = relationship(lazy="selectin")
     manufacturer: Mapped[Manufacturer] = relationship(lazy="selectin")
     scope_model: Mapped[ScopeModel | None] = relationship(lazy="selectin")