feat: export MediaType from http_parser

[Reprevise]

This is a similar change of which I introduced to the Dio package. A developer shouldn't have to import a transitive dependency (or make it a direct dependency) in order to use a method of a package.

Fixes #873

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[Reprevise]

Friendly ping @brianquinlan

[brianquinlan]

Hi @Reprevise

I'm not sure that this is idiomatic API design. Do you have examples of other packages (ideally from the Dart team) that export symbols from other packages?

[Reprevise]

@brianquinlan Here's Flutter exporting the meta package.

More flutter exports.

[brianquinlan]

I've convinced, thanks! Could you update pubspec.yaml and CHANGELOG.md?

[Reprevise]

Should I add this to 1.6.0-wip?

[brianquinlan]

Should I add this to 1.6.0-wip?

Ah, yes please. So you only need to add a CHANGELOG entry.

[github-actions]

PR Health

Breaking changes ✔️

Package	Change	Current Version	New Version	Needed Version	Looking good?
http	None	1.5.0	1.6.0-wip	1.5.0	✔️

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Changelog Entry ✔️

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Coverage ✔️

File	Coverage
pkgs/http/lib/http.dart	💚 100 %

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API leaks ✔️

The following packages contain symbols visible in the public API, but not exported by the library. Export these symbols or remove them from your publicly visible API.

Package	Leaked API symbol	Leaking sources

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License Headers ✔️

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

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pkgs/http/example/main.dart

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[Reprevise]

@brianquinlan Is this good to go?

[brianquinlan]

@brianquinlan Is this good to go?

Yes, thank you!