feat: Add canonical error codes for generic error handling. #2711
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Every error enum should have a conversion function to the canonical codes list. This can make client code more resilient to additions of error codes to per-function error enums, and simplify much of the error handling that currently needs to
switch()over each error enum separately.It's still useful to have additional information from the per-function error enums to present the user with better error messages, but for programmatic error handling (e.g. bots), the canonical codes should always be sufficient context.
This change is