[BUG] Desktop app does not save OpenRouter API key

Description

When attempting to add an OpenRouter API key through the Claude Code desktop app settings UI, the key is not saved/persisted.

Expected Behavior

The desktop app should:

1. Accept the OpenRouter API key when entered in the settings
2. Validate the key by checking its validity against the OpenRouter API
3. Fetch and display the available models associated with that API key

Actual Behavior

The OpenRouter API key is not persisted after being entered in the desktop app settings.

Environment

• OS: Windows 11 Pro (10.0.26200)
• Platform: Claude Code Desktop App
• Version: Latest (auto-update channel: latest)

Steps to Reproduce

1. Open Claude Code desktop app
2. Navigate to settings/API configuration
3. Attempt to add an OpenRouter API key
4. Key does not save / is lost on app restart

Workaround

Setting the key manually in ~/.claude/settings.json under env works, but the desktop UI should handle this properly — validating the key and fetching available models for selection.

Additional Context

Third-party API providers (like OpenRouter) are important for users who route through alternative endpoints. The desktop app should have first-class support for adding, validating, and managing these keys through the UI.

🤖 Generated with Claude Code