Desktop: model_catalog_json loaded but custom models not shown in picker (regression, related to #32349)

### What version of Codex? Desktop 26.715.61943 / CLI 0.145.0-alpha.27 (Windows 11) ### What issue are you seeing? model_catalog_json is configured correctly, codex debug models shows all 5 custom models from the catalog JSON, but the desktop app model picker is completely empty when using a custom provider with env_key. The issue is the same as #32349 but also affects the desktop app, not just CLI. config.toml has model_catalog_json pointing to a valid JSON file codex debug models outputs all 5 models correctly API requests work fine (provider: Volcengine CodingPlan via Responses API) Desktop model picker dropdown is empty ### Steps to reproduce 1. Configure a custom provider with model_catalog_json in ~/.codex/config.toml 2. The catalog JSON has use_responses_lite: false on every entry 3. Open Codex desktop app 4. Model picker dropdown is empty ### Related * Custom model metadata cannot be resolved although model_catalog_json is successfully loaded 已成功加载 model_catalog_json，但仍无法解析自定义模型元数据 #32349 (same symptom on CLI)

https://github.com/openai/codex/issues/19694

The patch works on the desktop Codex, but not in VS Code.