feat: Complete Google Search Console integration with Clerk authentication

- Add GSC API service with OAuth2 authentication
- Implement Clerk authentication for frontend and backend
- Add GSC login button and OAuth callback handling
- Create comprehensive GSC data fetching and caching
- Add authentication middleware for backend API protection
- Implement real-time GSC data integration in SEO dashboard
- Add user-specific GSC site management
- Include comprehensive logging and error handling
- Add TypeScript support and proper type definitions
- Create environment templates and setup documentation
- Update gitignore to exclude sensitive credential files

Features added:
- GSC OAuth2 authentication flow
- Real-time search analytics data
- Site list management
- Sitemap analysis
- User-specific data isolation
- Comprehensive error handling
- Authentication token management
- Popup-based OAuth flow
- Data caching and refresh mechanisms

Note: gsc_credentials.json should be created locally with your Google OAuth credentials

frontend/src/components/OnboardingWizard/BusinessDescriptionStep.tsx

@@ -90,7 +90,7 @@ const BusinessDescriptionStep: React.FC<BusinessDescriptionStepProps> = ({ onBac
             rows={4}
             margin="normal"
             required
-            helperText={`${formData.business_description.length}/1000 characters`}
+            helperText={`${formData.business_description?.length || 0}/1000 characters`}
             inputProps={{ maxLength: 1000 }}
             disabled={loading}
           />
@@ -101,7 +101,7 @@ const BusinessDescriptionStep: React.FC<BusinessDescriptionStepProps> = ({ onBac
             onChange={handleChange}
             fullWidth
             margin="normal"
-            helperText={`${formData.industry.length}/100 characters`}
+            helperText={`${formData.industry?.length || 0}/100 characters`}
             inputProps={{ maxLength: 100 }}
             disabled={loading}
           />