gh-36584: implemented power of graph function under basic methods
### Description
This PR introduces a new function, `power_of_graph`, to compute the kth
power of an undirected, unweighted graph efficiently using the shortest
distances method. The proposed function leverages Breadth-First Search
(BFS) to calculate the power graph, providing a practical and scalable
solution.
### Why is this change required?
The change is required to address the need for efficiently calculating
the kth power of a graph, a fundamental operation in graph theory. The
PR aims to incorporate this feature into the SageMath library.
Fixes #36582
### Checklist
- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion (if applicable).
- [x] I have created tests covering the changes.
- [x] I have updated the documentation accordingly.
### :hourglass: Dependencies
#36582 : To implement power of graph
URL: https://github.com/sagemath/sage/pull/36584
Reported by: saatvikraoIITGN
Reviewer(s): David Coudert, saatvikraoIITGN
