Add unit tests for fit_ellipse_to_points center estimation

[AlgoFoe]

Description

What is this PR

• Bug fix
• Addition of a new feature
• Other (tests)

Why is this PR needed?

• The fit_ellipse_to_points function did not have dedicated unit tests and this made it difficult to verify the correctness of the fitted ellipse parameters, particularly the ellipse center.

What does this PR do?

• It adds dedicated unit tests for fit_ellipse_to_points that validate correct recovery of the ellipse center.
• The tests contain:
  • general rotated ellipse
  • circular (equal-axes) edge case

References

• Closes : Add unit tests to fit_ellipse_to_points #36

How has this PR been tested?

• Tests were run locally using pytest.
• fitted ellipse and recovered center were also verified.

Is this a breaking change?

• No.

Does this PR require an update to the documentation?

• No.

Checklist:

• The code has been tested locally
• Tests have been added to cover all new functionality
• The documentation has been updated to reflect any changes
• The code has been formatted with pre-commit