Add some safeties around the charset-detection and transliteration

[uberbrady]

Should prevent some rollbars we get around iconv() - this puts a try/catch around the iconv() call and returns a new translation string for the error which hopefully will be informative for the end-user as they're trying to upload a CSV file.

I also added a test with a very gnarly fake WINDOWS-1251 string in it to trigger the new transliteration-failure mode.

[what-the-diff]

PR Summary

• Enhanced Error Handling for Encoding Transliteration
  Improved the process of error handling in our import features. We're now able to log any issues encountered, as well as manage and respond to specific situations where transliteration may fail.

• Added New Error Message
  Introduces a new message to alert users when transliteration failure is caused due to invalid characters.

• New Test Case for Error Handling
  We've added an additional test that specifically checks how the system manages incorrect encoding inputs. This test ensures the system responds appropriately to such situations, which will help maintain the robustness of the application in the face of potential encoding errors.