Add support for sorting by various fields

tests/test_search.py

@@ -15,6 +15,7 @@ from hxbooks.search import (
     IsOperatorValue,
     QueryParser,
     SearchQuery,
+    SortDirection,
     _convert_value,  # noqa: PLC2701
 )
 
@@ -267,6 +268,21 @@ class TestTypeConversion:
         result = _convert_value(Field.IS, "invalid-status")
         assert result == IsOperatorValue.UNKNOWN
 
+    def test_convert_sort_field(self, parser: QueryParser) -> None:
+        """Test converting values for 'sort' field."""
+        result = _convert_value(Field.SORT, "added")
+        assert result == (Field.ADDED_DATE, SortDirection.ASC)
+
+        result = _convert_value(Field.SORT, "added-desc")
+        assert result == (Field.ADDED_DATE, SortDirection.DESC)
+
+        # Invalid field or direction should fallback to a default value
+        result = _convert_value(Field.SORT, "added-invalid")
+        assert result == (Field.SORT, SortDirection.ASC)
+
+        result = _convert_value(Field.SORT, "invalid-asc")
+        assert result == (Field.SORT, SortDirection.ASC)
+
 
 class TestParsingEdgeCases:
     """Test edge cases and error handling in query parsing."""