feat(numerical_methods): Add Neville's algorithm for interpolation

[Keykyrios]

Description of Change

This pull request introduces an implementation of Neville's Algorithm for polynomial interpolation in C. The file is located in the numerical_methods directory, as it's a specific numerical method for solving interpolation problems.

The submission includes:

• A pure C implementation (nevilles_algorithm.c) with manual memory management.
• Doxygen-style comments that explain the file's purpose, the function, its parameters, and the author.
• A tests() function that uses assert.h to verify the algorithm's correctness with linear, quadratic, and negative-valued test cases.

Wikipedia Reference: https://en.wikipedia.org/wiki/Neville%27s_algorithm

Checklist

• Added description of change
• Added file name matches File name guidelines (nevilles_algorithm.c)
• Added tests and example, test must pass
• Relevant documentation/comments is changed or added
• PR title follows semantic commit guidelines
• Search previous suggestions before making a new one, as yours may be a duplicate.
• I acknowledge that all my contributions will be made under the project's license.

Notes: Adds a standard implementation of Neville's algorithm with self-contained tests.