Incompatible dependency in GUI extras: gradio-client==1.8.0 on Python 3.8

[Divocle]

Description

When installing the GUI extra dependencies on Python 3.8:

pip install -e .[gui]

the installation fails with:

ERROR: Could not find a version that satisfies the requirement gradio-client==1.8.0

Root Cause

Although gradio-client==1.8.0 exists on PyPI, it does not provide distributions
for Python 3.8 (no cp38 wheels). As a result, pip cannot resolve this dependency
on Python 3.8 environments.

At the same time, the project does not specify a minimum Python version in
setup.py, and the minimal installation works correctly on Python 3.8.

This makes the current GUI extra dependency specification incompatible with
Python 3.8.

Environment

• Python version: 3.8
• OS: Linux
• Installation method: pip install -e .[gui]

Suggested Fix (optional)

One possible solution is to make the gradio-client dependency conditional
based on Python version, or relax the strict version pinning for Python 3.8.