Fix inverted date filtering logic in load_gee_as_image()

[mihiarc]

Summary

• Fixed inverted conditional logic for date filtering in load_gee_as_image() functions

Problem

The date filtering logic was inverted - filters were being applied when dates were None rather than when they were provided:

# Before (incorrect)
if start_date is None and end_date is None:
    col = col.filterDate(start_date, end_date)
else:
    pass

This caused:

• Date filters to be ignored when users specified date ranges
• Attempts to filter with None values when no dates were provided

Solution

# After (correct)
if start_date is not None and end_date is not None:
    col = col.filterDate(start_date, end_date)

Files Changed

• skiba/point_extraction.py
• skiba/aggregated_point_extraction.py
• skiba/buffer_method.py

Testing

The fix is straightforward logic correction. Date filtering now works as expected:

• When dates are provided → filter is applied
• When dates are not provided → no filtering (uses full time range)

Fixes #75