Add robust fallback logic for Step 3 data passing

- Check multiple storage sources for website URL (props, localStorage, sessionStorage)
- Add validation to prevent API calls without website URL
- Improve debugging logs to track data flow
- Make CompetitorAnalysisStep more resilient to production edge cases
- No breaking changes, just defensive improvements

frontend/src/components/OnboardingWizard/Wizard.tsx

@@ -563,7 +563,7 @@ const Wizard: React.FC<WizardProps> = ({ onComplete }) => {
         key="research" 
         onContinue={handleNext} 
         onBack={handleBack}
-        userUrl={stepData?.website || ''}
+        userUrl={stepData?.website || localStorage.getItem('website_url') || ''}
         industryContext={stepData?.industryContext}
         onDataReady={handleCompetitorDataReady}
       />,