The "q" key was removed while addressing ticket #36411. Despite
`MediaType.params` is undocumented and considered internal, it was used
in third-party projects (Zulip reported breakage), so this work restored
the `q` key in `params`.
Thanks Anders Kaseorg for the report.
Regression in c075508b4de8edf9db553b409f8a8ed2f26ecead.
HttpRequest.get_preferred_type() did not account for parameters in
Accept header media types (e.g., "text/vcard; version=3.0"). This caused
incorrect content negotiation when multiple types differed only by
parameters, reducing specificity as per RFC 7231 section 5.3.2
(https://datatracker.ietf.org/doc/html/rfc7231.html#section-5.3.2).
This fix updates get_preferred_type() to treat media types with
parameters as distinct, allowing more precise and standards-compliant
matching.
Thanks to magicfelix for the report, and to David Sanders and Sarah
Boyce for the reviews.
