add few more files in algo/arrays

[AKSHITHA-CHILUKA]

Have you read the Contributing Guidelines on issues?

• [X] I have read the Contributing Guidelines on issues.

Description

add sliding-Window-Technique.md : -sliding window approach for problems such as finding the maximum sum of a subarray of fixed size. Dynamic-Arrays.md :

• dynamic arrays (like ArrayLists in Java) work, including resizing mechanisms. Array-Manipulation-Techniques.md:
• techniques like reversing an array, merging two sorted arrays, and more.

Self-service

• [x] I'd be willing to address this documentation request myself.

[github-actions[bot]]

👋 Hi @AKSHITHA-CHILUKA! Thanks for opening this issue. We appreciate your contribution to the Algo project. Our team will review it soon.