feat: add pin course feature

[IkramBagban]

PR Fixes:

-In this PR, I have added the pin and unpin course feature.

• Using localStorage to store pinned course IDs.

Resolves #1710

Checklist before requesting a review

• [✅] I have performed a self-review of my code
• [✅] I assure there is no similar/duplicate pull request regarding same issue

https://github.com/user-attachments/assets/481332bf-4e8c-4f22-beb5-1cb915d8372e