Add collaboration modes test prompts (#9443)

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codex-rs/core/src/models_manager/mod.rs

@@ -3,3 +3,6 @@ pub mod collaboration_mode_presets;
 pub mod manager;
 pub mod model_info;
 pub mod model_presets;
+
+#[cfg(any(test, feature = "test-support"))]
+pub use collaboration_mode_presets::test_builtin_collaboration_mode_presets;