Example, multi-family broken

[dnil]

(genmod) ➜  genmod git:(master) ✗ genmod models -f examples/dominant_trio.ped -o examples/test_vcf_dominant_annotated.vcf examples/test_vcf_annotated.vcf
(genmod) ➜  genmod git:(master) ✗     genmod annotate -o examples/test_vcf_annotated.vcf --annotate_regions examples/test_vcf.vcf
        genmod models -f examples/multi_family.ped -o examples/test_vcf_multi_annotated.vcf examples/test_vcf_annotated.vcf
Process VariantAnnotator-2:
Traceback (most recent call last):
  File "/usr/local/miniconda3/envs/genmod/lib/python3.13/multiprocessing/process.py", line 313, in _bootstrap
    self.run()
    ~~~~~~~~^^
  File "/Users/dannil/.local/share/uv/tools/genmod/lib/python3.13/site-packages/genmod/annotate_models/variant_annotator.py", line 108, in run
    variant["genotypes"] = get_genotypes(variant, self.individuals)
                           ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dannil/.local/share/uv/tools/genmod/lib/python3.13/site-packages/genmod/vcf_tools/get_genotypes.py", line 23, in get_genotypes
    gt_info = variant[individual].split(":")
              ~~~~~~~^^^^^^^^^^^^
KeyError: 'proband_2'
^CProcess VariantPrinter-6:

Aborted!
Traceback (most recent call last):
  File "/usr/local/miniconda3/envs/genmod/lib/python3.13/multiprocessing/process.py", line 313, in _bootstrap
    self.run()
    ~~~~~~~~^^
  File "/Users/dannil/.local/share/uv/tools/genmod/lib/python3.13/site-packages/genmod/utils/variant_printer.py", line 68, in run
    variant = self.task_queue.get()
  File "<string>", line 2, in get
  File "/usr/local/miniconda3/envs/genmod/lib/python3.13/multiprocessing/managers.py", line 824, in _callmethod
    kind, result = conn.recv()
                   ~~~~~~~~~^^
  File "/usr/local/miniconda3/envs/genmod/lib/python3.13/multiprocessing/connection.py", line 250, in recv
    buf = self._recv_bytes()
  File "/usr/local/miniconda3/envs/genmod/lib/python3.13/multiprocessing/connection.py", line 430, in _recv_bytes
    buf = self._recv(4)
  File "/usr/local/miniconda3/envs/genmod/lib/python3.13/multiprocessing/connection.py", line 395, in _recv
    chunk = read(handle, remaining)
KeyboardInterrupt

[dnil]

Low priority, but still something to look at, either fixing the example if it is truly fully benign or the code for multiple families. Consider in conjunction with #148 perhaps: we have extensive experience with single family, but very little with multiple.