vds file with a window column can not be opened

[reagle]

Small description

vds file with a window column can not be opened

Data to reproduce

https://people.sc.fsu.edu/~jburkardt/data/csv/biostats.csv

Steps to reproduce

1. vd https://people.sc.fsu.edu/~jburkardt/data/csv/addresses.csv
2. c weig
3. w -1 -1
4. save as vds file; exit
5. open vds file and see error with -N: "KeyError: 'WindowColumn'"

Trace

Traceback (most recent call last):
  File "/Users/reagle/.local/share/uv/tools/visidata/lib/python3.13/site-packages/visidata/threads.py", line 227, in _toplevelTryFunc
    t.status = func(*args, **kwargs)
               ~~~~^^^^^^^^^^^^^^^^^
  File "/Users/reagle/.local/share/uv/tools/visidata/lib/python3.13/site-packages/visidata/sheets.py", line 281, in reload
    self.loader()
    ~~~~~~~~~~~^^
  File "/Users/reagle/.local/share/uv/tools/visidata/lib/python3.13/site-packages/visidata/sheets.py", line 306, in loader
    for i, r in enumerate(self.iterload()):
                ~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "/Users/reagle/.local/share/uv/tools/visidata/lib/python3.13/site-packages/visidata/loaders/vds.py", line 83, in iterload
    c = globals()[classname](d.pop('name'), sheet=self)
        ~~~~~~~~~^^^^^^^^^^^
KeyError: 'WindowColumn'

Additional context

• macOS 15.3 24D60 arm64