feat: model picker (#8209)

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

@@ -42,6 +42,7 @@ fn preset_to_info(preset: &ModelPreset, priority: i32) -> ModelInfo {
     }
 }
 
+// todo(aibrahim): fix the priorities to be the opposite here.
 /// Write a models_cache.json file to the codex home directory.
 /// This prevents ModelsManager from making network requests to refresh models.
 /// The cache will be treated as fresh (within TTL) and used instead of fetching from the network.