Add Boruvka's minimum spanning tree algorithm

[tabishfarhan7]

Description of Change

This pull request adds an implementation of Borůvka's Minimum Spanning Tree (MST) algorithm for weighted undirected graphs.

The implementation is based on a Disjoint Set Union (Union-Find) data structure . Path compression and union by rank are used to efficiently merge connected components . It also includes Doxygen documentation, complexity analysis and self-tests using assert().

Checklist

• Added description of change
• Added file name matches file name guidelines
• Added tests and example, test must pass
• Added documentation so that the program is self-explanatory and educational
• 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 new graph algorithm implementation: Borůvka's Minimum Spanning Tree.