Fix bugs and typo errors in closest_pair_of_points.py

[Roy027]

Describe your change:

• Add an algorithm
• Fix a bug or typo in an existing algorithm
• Add or change doctests
• Documentation change

Summary

This PR fixes several logic errors in divide_and_conquer/closest_pair_of_points.py.

The strip search loop previously skipped valid comparisons due to incorrect
loop bounds. The recursive call also passed an incorrect sorted list,
breaking the divide-and-conquer step of the algorithm.

The doctest for dis_between_closest_in_strip() previously expected 85,
which only occurred because the buggy implementation skipped valid point
comparisons. After fixing the logic, the correct result is 5.

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file.
• All functions and variable names follow Python naming conventions.
• All functions and variable names follow Python naming conventions. (Checked: Added type hints)
• All functions have doctests that pass the automated testing.

[Roy027]

sorry accidentally modified DIRECTORY.md but i have removed changes.