Support Python 3.12

[MarcSkovMadsen]

This is reopening #109 as its still a problem with ipywidgets-bokeh == 1.6.0

Reproduce

uv venv
source .venv/bin/activate
uv pip install panel watchfiles ipywidgets_bokeh pyglobegl

import panel as pn
from pyglobegl import GlobeWidget

pn.extension("ipywidgets")

globe = GlobeWidget()
pn.pane.IPyWidget(globe).servable()

$ panel serve script.py --dev
Traceback (most recent call last):
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/panel/io/handlers.py", line 539, in run
    exec(self._code, module.__dict__)
  File "/home/jovyan/repos/tmp/script.py", line 4, in <module>
    pn.extension("ipywidgets")
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/pyviz_comms/__init__.py", line 65, in __new__
    return param.ParameterizedFunction.__new__(cls, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/param/parameterized.py", line 5929, in __new__
    return inst.__call__(*args,**params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/panel/config.py", line 799, in __call__
    __import__(module)
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/panel/io/ipywidget.py", line 22, in <module>
    from ipywidgets_bokeh.kernel import (
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/ipywidgets_bokeh/__init__.py", line 1, in <module>
    from .widget import IPyWidget
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/ipywidgets_bokeh/widget.py", line 13, in <module>
    from .kernel import kernel
  File "/home/jovyan/repos/tmp/.venv/lib/python3.12/site-packages/ipywidgets_bokeh/kernel.py", line 12, in <module>
    from distutils.version import LooseVersion
ModuleNotFoundError: No module named 'distutils'
2026-02-07 05:37:48,424 Starting Bokeh server version 3.8.2 (running on Tornado 6.5.4)
2026-02-07 05:37:48,425 User authentication hooks NOT provided (default user enabled)
2026-02-07 05:37:48,427 Bokeh app running at: http://localhost:5006/script
2026-02-07 05:37:48,427 Starting Bokeh server with process id: 2056