remove ANNError enums

Nobody has claimed this yet.

## Is your feature request related to a problem? Please describe.
ANNerror enums need to be removed since that is not the preferred error handling pattern. All usages and tests should be replaced

## Describe the solution you'd like
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## Describe alternatives you've considered
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## Provide references (if applicable)
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## Additional context
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Search the repository for the ANNError enums and all of their usages, including tests, then inspect the surrounding error-handling code to identify the replacement pattern already preferred by the project. The work is complete when the enums, usages, and tests have been replaced and the relevant test suite passes.

Written by the indexing model from the issue text.