WIP: [objective_c] Reproing compiler crash

[liamappelbe]

In pkgs/objective_c, run dart test/converter_test.dart

[github-actions]

PR Health

Breaking changes ✔️

Package	Change	Current Version	New Version	Needed Version	Looking good?
objective_c	Breaking	8.1.0	9.0.0-dev.0	9.0.0	✔️

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Changelog Entry ❗

Package	Changed Files
package:objective_c	pkgs/objective_c/lib/objective_c.dart pkgs/objective_c/lib/src/converter.dart pkgs/objective_c/lib/src/internal.dart pkgs/objective_c/lib/src/ns_array.dart pkgs/objective_c/lib/src/ns_dictionary.dart pkgs/objective_c/lib/src/ns_enumerator.dart pkgs/objective_c/lib/src/ns_input_stream.dart pkgs/objective_c/lib/src/ns_set.dart pkgs/objective_c/lib/src/objective_c_bindings_generated.dart

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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
objective_c	_FinalizablePointer	internal.dart::_ObjCReference::new::_finalizable

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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.

Files
pkgs/objective_c/lib/src/ns_input_stream.dart

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