Limit supported Python versions to < 3.14

[clarasb]

This PR restricts the supported Python versions to >=3.10,<3.14 in both pyproject.toml and environment.yaml.

Altair 5.5 currently fails to import with Python 3.14 due to a TypedDict API change (closed= argument no longer supported). See the Error Message below for further details.

Limiting Python to 3.13 ensures a working environment.

---

Error:

Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo\server\main.py", line 11, in <module>
    main()
    ~~~~^^
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo\server\main.py", line 7, in main
    asyncio.run(run_app())
    ~~~~~~~~~~~^^^^^^^^^^^
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\asyncio\runners.py", line 204, in run
    return runner.run(main)
           ~~~~~~~~~~^^^^^^
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\asyncio\runners.py", line 127, in run
    return self._loop.run_until_complete(task)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\asyncio\base_events.py", line 719, in run_until_complete
    return future.result()
           ~~~~~~~~~~~~~^^
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo\server\app.py", line 133, in run_app
    app = make_app()
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo\server\app.py", line 123, in make_app
    ext_ctx = ExtensionContext.load(Context(), server_config.get("extensions", []))
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\chartlets\extensioncontext.py", line 56, in load
    module = importlib.import_module(module_name)
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\importlib\__init__.py", line 88, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen importlib._bootstrap>", line 1398, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1371, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1342, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 938, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 762, in exec_module
  File "<frozen importlib._bootstrap>", line 491, in _call_with_frames_removed
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo\my_extension\__init__.py", line 2, in <module>
    from .my_panel_1 import panel as my_panel_1
  File "C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo\my_extension\my_panel_1.py", line 2, in <module>
    import altair as alt
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\site-packages\altair\__init__.py", line 649, in <module>
    from altair.vegalite import *
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\site-packages\altair\vegalite\__init__.py", line 2, in <module>
    from .v5 import *
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\site-packages\altair\vegalite\v5\__init__.py", line 3, in <module>
    from altair.vegalite.v5 import api, compiler, schema
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\site-packages\altair\vegalite\v5\api.py", line 19, in <module>
    from altair import theme, utils
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\site-packages\altair\theme.py", line 9, in <module>
    from altair.vegalite.v5.schema._config import (
    ...<70 lines>...
    )
  File "C:\Users\Clara\miniconda3\envs\chartlets\Lib\site-packages\altair\vegalite\v5\schema\_config.py", line 6491, in <module>
    class StepKwds(TypedDict, closed=True, total=False):  # type: ignore[call-arg]
    ...<21 lines>...
        __extra_items__: StepFor_T
TypeError: _TypedDictMeta.__new__() got an unexpected keyword argument 'closed'
(chartlets) PS C:\Users\Clara\Desktop\bc\chartlets\chartlets.py\demo> 

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.70%. Comparing base (4873af5) to head (8540cda).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #125   +/-   ##
=======================================
  Coverage   92.70%   92.70%           
=======================================
  Files          86       86           
  Lines        1495     1495           
  Branches      224      224           
=======================================
  Hits         1386     1386           
  Misses         91       91           
  Partials       18       18           

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