feat: add LeetCode problem 167

[Vaibhav-Patidar]

Description of Change

Implemented the Two Sum II solution using the two-pointer approach. The function takes a sorted array and returns the 1-based indices of the two numbers whose sum equals the given target. It uses a single pass with O(n) time complexity and O(1) extra space. The result array is dynamically allocated, with memory management handled by the caller.

Checklist

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• Added tests and example, test must pass
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Notes: Added the solution for Leetcode problem no.167 Two-Sum-II