BUG: Fix PyArrow array access in Categorical constructor for Index objects (#60563)

Author: chilin0525

pandas/core/arrays/categorical.py

@@ -447,7 +447,12 @@ def __init__(
             if isinstance(values.dtype, ArrowDtype) and issubclass(
                 values.dtype.type, CategoricalDtypeType
             ):
-                arr = values._pa_array.combine_chunks()
+                from pandas import Index
+
+                if isinstance(values, Index):
+                    arr = values._data._pa_array.combine_chunks()
+                else:
+                    arr = values._pa_array.combine_chunks()
                 categories = arr.dictionary.to_pandas(types_mapper=ArrowDtype)
                 codes = arr.indices.to_numpy()
                 dtype = CategoricalDtype(categories, values.dtype.pyarrow_dtype.ordered)