Handling Ruff Errors and Ignores

This is to keep in track of all the changes made because of the Ruff Errors.
Here are the current changes to the Ruff Errors:
- [x] I001 [ All files (including test files)]
Formatted Imports
- [x] [__init__.py]
Formatted list
`__all__ = ["download_images", "validate_download", "check_alignment", "downsample_and_save_image"]`
`__all__ = ["check_alignment", "download_images", "downsample_and_save_image", "validate_download"]`
- [x] BLE001[exceptions.py]
Created Custom Exceptions
- [x] B018 [__init__.py]
Exposing instance methods as temporary placeholders
`# Expose instance methods`
`_ = buddy_check_instance.validate_download`
`_ = buddy_check_instance.check_alignment`
- [x] SIM115 [test_buddycheck.py]
Include delete clause and temp path using context manager (Thank you Elizabeth and Net!)
`with tempfile.NamedTemporaryFile(delete=False, mode='w', suffix=".csv") as f:`
` with tempfile.NamedTemporaryFile(delete=False, mode='w', suffix=".csv") as f:`
- [x] RUF059 [test_roll_call.py]
Unused variable called using temporary placeholders
`expected_cols, _= self.rollcall.setup_expected_columns(args)`
`expected_cols, _= self.rollcall.setup_expected_columns(args)`

Review the Ruff changes listed for __init__.py, exceptions.py, test_buddycheck.py, and test_roll_call.py, along with the import formatting changes across the project. Check whether the listed fixes are present and whether Ruff reports any remaining errors; done means the tracked errors are resolved without new lint failures.

Written by the indexing model from the issue text.