add json field to store any additional blob of data that may be missing; also populate db when dumping listings

crawler/models/listing.py

@@ -31,6 +31,9 @@ class Listing(SQLModel, table=False):
     listing_site: ListingSite = Field(nullable=False)
     last_seen: datetime = Field(default_factory=datetime.now, nullable=False)
     photo_thumbnail: str | None = Field(default=None, nullable=True)
+    additional_info: Dict[str, Any] = Field(
+        default_factory=dict, sa_type=JSON, nullable=False
+    )
 
 
 class FurnishType(enum.StrEnum):