Add Algorithms & Data Structures collection

This pull request adds a new curated collection: Algorithms & Data Structures (collections/algorithms-and-data-structures/).

The collection brings together well-maintained, high-quality open-source implementations, visualization tools, and interview preparation guides focused on fundamental computer science algorithms and data structures across multiple programming languages.

Author: ajay-dhangar

collections/algorithms-and-data-structures/index.md

@@ -0,0 +1,14 @@
+---
+items:
+ - ajay-dhangar/algo
+ - codeharborhub/dsa
+ - TheAlgorithms/Python
+ - TheAlgorithms/Java
+ - trekhleb/javascript-algorithms
+ - jwasham/coding-interview-university
+display_name: Algorithms & Data Structures
+created_by: ajay-dhangar
+image: https://ajay-dhangar.github.io/algo/logo/logo.png
+---
+
+A curated collection of open-source algorithms, data structures, and implementation guides to help developers master computational problem-solving and technical interviews.