Rename OpenAI models to models manager (#8346)

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codex-rs/app-server/tests/common/models_cache.rs

@@ -1,6 +1,6 @@
 use chrono::DateTime;
 use chrono::Utc;
-use codex_core::openai_models::model_presets::all_model_presets;
+use codex_core::models_manager::model_presets::all_model_presets;
 use codex_protocol::openai_models::ClientVersion;
 use codex_protocol::openai_models::ConfigShellToolType;
 use codex_protocol::openai_models::ModelInfo;