fix: add res.status to error message

[gutenye]

cause res.statusText can be undefined

[Copilot]

Pull Request Overview

This PR fixes an issue where error messages could be incomplete when res.statusText is undefined by including the HTTP status code in error messages.

• Updates error message construction to include both status code and status text
• Handles cases where res.statusText may be undefined by providing a fallback

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[Copilot]

The error message format could result in trailing whitespace when res.statusText is undefined. Consider using a more explicit format like ${res.status}${res.statusText ? ': ' + res.statusText : ''} to avoid unnecessary spaces.

Suggested change

	const err = new Error(`${res.status} ${res.statusText || ''}`)
	const err = new Error(`${res.status}${res.statusText ? ': ' + res.statusText : ''}`)

[akinncar]

cause res.statusText can be undefined

if statusText is currently undefined, in this new implementation, statusText will be end up as the same as status, right?
so why do we need this?

[gutenye]

if statusText is currently undefined, in this new implementation, statusText will be end up as the same as status, right? so why do we need this?

no, before the error message is empty, after the error message is status, at lease it's not empty.

[dagohan]

utACK

[ChALkeR]

this is a frozen fetchival impl
replacement api is in experimental/ dir to ensure compat

this file will be removed in a major release, see #25

any changes that are exclusive to the file being removed don't make sense

[gutenye]

left a comment in that PR
https://github.com/ExodusMovement/fetch/pull/25/files#r2409214300