[Feature Request] Allow Sorting by Acceptance & Multi-Select Difficulty Filters

[harsh-dexter]

Summary

It would greatly enhance usability if users could:

1. Sort the questions by Acceptance Rate (ascending or descending).
2. Select multiple difficulties at once (e.g., Medium + Hard together) instead of choosing just one.

Why is this useful?

• Sorting by Acceptance Rate helps beginners pick easier-to-approach questions first.
• Filtering by multiple difficulties allows users to better target their comfort/challenge zone while practicing.