- Render the custom model dropdown menu in a portal so it escapes clipped stacking contexts
- Update dashboard styles to give the floating model menu reliable overlay positioning above quick entry surfaces
- Refresh dropdown-focused tests to cover portal layering behavior in quick entry and model selector flows
- Document the layering behavior in the dashboard README for future UI maintenance
- Create ProviderIcon component with provider-to-icon mappings (OpenAI, Anthropic, Google, etc.)
- Build CustomModelDropdown with icon display, filtering, and keyboard navigation
- Integrate custom dropdown into ModelSelectorTab replacing native select element
- Add CSS styles for provider icons in dropdown items and model badges
- Add comprehensive tests for ProviderIcon, CustomModelDropdown, and ModelSelectorTab
