[Good First Issue]: Improve user-facing error messages

[youngcoder45]

Summary

Make error messages more user-friendly.

Context

Technical or unclear error messages confuse users.

Scope (what's in / out)

Files:

• command handlers
• error handling logic

Acceptance criteria

• Errors are easy to understand
• No raw technical messages shown to users

Suggested approach / hints

1. Search for error responses
2. Replace with:
   • simple language
   • helpful hints

Estimated difficulty

XS (≤ 1 hour)

Maintainer checklist

• Task is well-scoped and actionable
• Has clear acceptance criteria
• Includes pointers to relevant code/docs
• Does not require private credentials/tokens