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## Summary by cubic
Added OpenRouter as a first-class option in the setup banner and
introduced a reusable provider card component. This streamlines provider
selection and adds E2E coverage for the setup flow.

- **New Features**
- Added SetupProviderCard and used it for Google and OpenRouter in
SetupBanner.
- Clicking Google or OpenRouter routes to the correct provider settings
and logs PostHog events.
  - Kept “Other providers” link to Settings.
- Added setup.spec.ts E2E test to verify Google, OpenRouter, and Other
navigation; introduced test config flag showSetupScreen to control the
OPENAI_API_KEY shortcut.

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