Add Levenshtein Distance algorithm implementation

[shimmer12]

Implement the Levenshtein distance algorithm in R with example usage and testing.

[Copilot]

Pull Request Overview

This PR implements the Levenshtein Distance algorithm in R, a dynamic programming solution that calculates the minimum number of single-character edits (insertions, deletions, or substitutions) required to transform one string into another. The implementation includes comprehensive documentation explaining the algorithm's complexity and real-world applications, along with example usage demonstrating various test cases including edge cases with empty strings.

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

[Copilot]

The roxygen2 documentation format is incorrect. Parameter descriptions should use @param s1 First string without the colon, and the return description should use @return The integer Levenshtein distance without the colon."

Suggested change

	#' @param s1: First string
	#' @param s2: Second string
	#' @return: The integer Levenshtein distance
	#' @param s1 First string
	#' @param s2 Second string
	#' @return The integer Levenshtein distance

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

[Copilot]

The filename uses uppercase 'R' extension. According to repository guidelines, all code file names must use lowercase '.r' extension.

[siriak]

It's already implemented here https://github.com/TheAlgorithms/R/blob/master/string_manipulation/levenshtein.r