🚚 Refactor and simplify backend file structure (#609)

src/backend/app/schemas/item.py

@@ -0,0 +1,39 @@
+from typing import Optional
+
+from pydantic import BaseModel
+
+
+# Shared properties
+class ItemBase(BaseModel):
+    title: Optional[str] = None
+    description: Optional[str] = None
+
+
+# Properties to receive on item creation
+class ItemCreate(ItemBase):
+    title: str
+
+
+# Properties to receive on item update
+class ItemUpdate(ItemBase):
+    pass
+
+
+# Properties shared by models stored in DB
+class ItemInDBBase(ItemBase):
+    id: int
+    title: str
+    owner_id: int
+
+    class Config:
+        orm_mode = True
+
+
+# Properties to return to client
+class Item(ItemInDBBase):
+    pass
+
+
+# Properties properties stored in DB
+class ItemInDB(ItemInDBBase):
+    pass