[v11] Sparse fieldsets allow for invalid types

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• Feature request.
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Description

When specifying sparse fieldsets, if you specify the type as the singular version of the type (i.e. fields[user]=name instead of fields[users]=name, the request succeeds instead of returning a 400.

Bug reports:

On the v0-11-dev branch with Ruby 3.3.5. The root of the issue is that classify is used to look up the resource class, which works the same for user and users, they both become UserResource, but then parse_fields doesn't verify that the type matches after getting the resource class back.

Suche im Branch v0-11-dev nach parse_fields und verfolge, wie der Sparse-Fieldset-Typ zu einer Ressourcenklasse aufgelöst wird. Füge Tests für fields[user]=name hinzu und verifiziere, dass der Singulartyp HTTP 400 zurückgibt, während die gültige Pluralform weiterhin erfolgreich ist.