fix: avoided printing stack trace and escaped input

[mohamedzeidan2021]

Issue #, if available:

Description of changes:
The first change was to print only the error type rather than the entire stack trace as it may reveal the application as well as any internal components it relies on.
The second change escape the user input before returning it to avoid a cross-site scripting vulnerability.

Testing done:
Tested changes in my own fork and CodeQL recognizes them as fixes.

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