C++ Domain: Error when parsing enum in template class scope

Describe the bug

I am trying to document an enum, that is part of a partially specialized template class.
However, I am getting this issue:

index.rst:6: WARNING: Invalid C++ declaration: Expected identifier in nested name, got keyword: template [error at 8]
  template<> Some<int>::Enum
  --------^

This only occurs for enums.
It works when I declare a class the same way.

How to Reproduce

.. This works:

.. cpp:class:: template<> Some<int>::Class


.. This doesn't:

.. cpp:enum:: template<> Some<int>::Enum

Environment Information

Platform:              linux; (Linux-5.15.167.4-microsoft-standard-WSL2-x86_64-with-glibc2.35)
Python version:        3.10.12 (main, Sep 11 2024, 15:47:36) [GCC 11.4.0])
Python implementation: CPython
Sphinx version:        8.1.3
Docutils version:      0.21.2
Jinja2 version:        3.1.4
Pygments version:      2.18.0

Sphinx extensions

No response

Additional context

No response

Start with the C++ domain's handling of the cpp:enum declaration and compare it with the working cpp:class case. Reproduce the warning using the provided reStructuredText example, then verify that documenting an enum in a partially specialized template class scope parses without the warning.