Added ability to search for users

[Rishikant181]

❓ Type of Change

• 📖 Documentation (docs, README, or comments)
• 🐞 Bug fix (non-breaking fix for an issue)
• 👌 Enhancement (improvement to existing functionality)
• ✨ New feature (adds new functionality)
• 🧹 Chore (build, tooling, dependencies)
• ⚠️ Breaking change (affects existing usage)

📚 Description

Added function to user module to search for users. The function uses the same endpoint as tweet.search. However, instead of appending user search functionality to tweet.search, a new function was added because searching for user returns fundamentally different data type (Tweet vs User). Adding a new function instead of re-using existing tweet.search maintains backwards compatibility, and makes more logical sense (tweet.search v/s user.search).

📝 Checklist

• Issue/discussion linked above.
• Documentation updated (if needed).
• Code follows project conventions and ESLint rules.
• No sensitive data or credentials are included.