handle None values in ClassifierSettings initialization

[bergsalex]

Fixes a bug where passing None values to ClassifierSettings causes a TypeError when filtering bouts.

Fixes #45

Problem

When using the library API or when behavior configuration dictionaries are missing optional keys, None values could be passed to ClassifierSettings.__init__(). These None values would later cause:

TypeError: '>' not supported between instances of 'NoneType' and 'int'

Solution

Modified ClassifierSettings.init() in src/jabs_postprocess/utils/metadata.py to handle None gracefully:

• If interpolate is None, use DEFAULT_INTERPOLATE
• If stitch is None, use DEFAULT_STITCH
• If min_bout is None, use DEFAULT_MIN_BOUT