fix(errors): handle Content-Type parameters

[fallintoplace]

Change summary

Fix HTTP error decoding when the Content-Type header includes parameters. This keeps structured API error fields in the decoded error.

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User Impact

Parameterized Content-Type values now use the correct decoder, preserving JSON:API and problem details fields.

Are there any considerations that need to be addressed for release?

No breaking changes.

[WhiteAbeLincoln]

Thanks @fallintoplace! Please use our PR template:

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[rcaril]

Hi @fallintoplace - thanks for your contribution. I took a look through our recorded API responses and didn't find any error responses where the Content-Type included parameters. Can you point out where you are seeing this behavior (which endpoint and the exact Content-Type header returned)?

[fallintoplace]

Fastly documents PATCH /service-authorizations responses with Content-Type: application/vnd.api+json; ext=bulk: https://docs-archive.fastly.com/snapshots/static/2020-04-30-api-aio.pdf

[rcaril]

Fastly documents PATCH /service-authorizations responses with Content-Type: application/vnd.api+json; ext=bulk: https://docs-archive.fastly.com/snapshots/static/2020-04-30-api-aio.pdf

Thanks for providing the reference @fallintoplace. FYI - the document you linked is archived - the live doc lives here: https://www.fastly.com/documentation/reference/api/account/service-authorization/.

With that being said, go-fastly does not call the bulk PATCH / DELETE endpoints that you referenced here. Are there any other live examples that you are utilizing that are impacted by the behavior you are pointing out?