chore: add source for LC problems

Added source attribution for LC Problems data.

Author: hitarth-gg

README.md

@@ -2,3 +2,7 @@
 
 <img width="1920" height="912" alt="image" src="https://github.com/user-attachments/assets/c91608fe-9849-4f2b-8b5d-8ac93bb03432" />
 <img width="1920" height="912" alt="image" src="https://github.com/user-attachments/assets/ac24ad15-0686-40c2-b477-7b5e978e6ccc" />
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+LC Problems data taken from: https://github.com/snehasishroy/leetcode-companywise-interview-questions