refactor(onboarding): restructure onboarding routes and components

- Removed obsolete onboarding routes: complete, create-complex, index, verify-email, and verify.
- Introduced new setup stepper page for onboarding process.
- Created a multi-step setup component to handle complex creation with validation.
- Added new schemas for complex creation and plan features.
- Implemented detailed steps for complex name, location, plan selection, and court setup.
- Enhanced error handling and user feedback during the onboarding process.

apps/frontend/src/routes/onboard/setup.tsx

@@ -0,0 +1,14 @@
+import { SetupStepperPage } from '@/features/onboard/setup-stepper-page';
+import { createFileRoute, redirect } from '@tanstack/react-router';
+
+export const Route = createFileRoute('/onboard/setup')({
+  beforeLoad: ({ context }) => {
+    const hasSession = context.auth.isAuthenticated;
+    const hasPendingSignup = Boolean(sessionStorage.getItem('pending-signup-email'));
+
+    if (!hasSession && !hasPendingSignup) {
+      throw redirect({ to: '/login' });
+    }
+  },
+  component: SetupStepperPage,
+});