Error toasts: show HTTP response detail + don't auto-close

[norrisng-bc]

Description

The detailed COMS error response message (specifically, the detail field) is now displayed in the toast body instead. Previously, only the HTTP response code and a generic AxiosError message is displayed.

Example: updating a bucket using invalid S3 credentials

Before:

Error: Configuring storage location source
AxiosError: Request failed with status code 409

After:

Error: Configuring storage location source
Unable to validate supplied credentials for the bucket

Also, error notifications no longer disappear automatically; they must be closed manually instead.

This should make it easier for users to diagnose basic errors, without having to reach out to us every time.

SHOWCASE-3941

Types of changes

New feature (non-breaking change which adds functionality)

Checklist

• I have read the CONTRIBUTING doc
• I have checked that unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

error.response?.data.detail ?? error

If the error isn't coming from the COMS API (or if COMS fails to return a properly-formatted error response as per the API spec), the toast message will fallback to the raw error itself, as was the case previously.

[github-actions]

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