Update the List (Unclaimed) Items Query

[kavinphan]

Description

Update the existing "List Unclaimed Items" query to support filtering by expiration date based on a start and end date given as the query params expirationDateAfter and expirationDateBefore. Both query params will be datetimes formatted as ISO-8601 strings.

Also update it to use the new Item table. It should return all fields.

Success Criteria

• 400 if either expirationDateAfter or expirationDateBefore are invalid ISO-8601 timestamps
• The expirationDateAfter and expirationDateBefore params are applied to the expirationDate column
• The route handler's documentation is updated
• There is a test file that covers the success criteria