Update setup banner: navigate to settings#ai & Dyad Pro option (#1361)

<!-- This is an auto-generated description by cubic. -->

## Summary by cubic
Updated the setup banner to navigate to Settings and auto-scroll to the
AI Providers section, and added a Dyad Pro setup option to streamline
onboarding.

- **New Features**
  - Added “Setup Dyad Pro” card with logo; opens Dyad Pro signup.
- “Other providers” now jumps to Settings → Provider section with smooth
scroll.
  - OpenRouter setup card updated with new teal styling.

- **Refactors**
- Introduced useScrollAndNavigateTo hook to navigate, scroll, and set
active section.
- Centralized active section state via activeSettingsSectionAtom (used
by SettingsList).
  - SetupProviderCard supports a new “dyad” variant styling.

<!-- End of auto-generated description by cubic. -->

src/atoms/viewAtoms.ts

@@ -4,3 +4,6 @@ export const isPreviewOpenAtom = atom(true);
 export const selectedFileAtom = atom<{
   path: string;
 } | null>(null);
+export const activeSettingsSectionAtom = atom<string | null>(
+  "general-settings",
+);