refactor: compact component spacing throughout app

PHASE 3 - COMPONENT SPACING OPTIMIZATION:

components/IdentityCheckOverlay.tsx:
- Modal padding: p-8 sm:p-10 → p-4 md:p-6
- Spacing: space-y-8 → space-y-3 md:space-y-4

components/CameraView.tsx:
- Container gaps: gap-6 → gap-3 md:gap-4

components/AIOnboarding.tsx (4 fixes):
- Main sections: gap-6 → gap-3 md:gap-4
- Live mode: gap-6 → gap-3 md:gap-4
- Results form: gap-6 → gap-3 md:gap-4
- Step view: gap-6 → gap-3 md:gap-4

components/ScannerSection.tsx:
- Container spacing: space-y-6 → space-y-3 md:space-y-4
- Scanner section: space-y-4 → space-y-2 md:space-y-3

components/LogsTable.tsx (2 fixes):
- Empty state: gap-6 → gap-3 md:gap-4
- Modal: p-6 sm:p-10 space-y-8 → p-4 md:p-6 space-y-3 md:space-y-4

Results:
- All 291 tests passing
- Zero TypeScript errors
- Mobile-first spacing applied throughout
- Consistent responsive pattern across all components

frontend/components/IdentityCheckOverlay.tsx

@@ -61,7 +61,7 @@ const IdentityCheckOverlay = memo(({ show, users, onAuthenticated }: IdentityChe
 
   return (
     <div data-testid="identity-check-overlay" className="fixed inset-0 z-[100] flex items-center justify-center p-4 bg-background/90 animate-in fade-in duration-500">
-      <div className="bg-surface border border-slate-800 rounded-[2.5rem] p-8 sm:p-10 max-w-sm w-full shadow-2xl space-y-8 animate-in zoom-in-95 duration-300 relative overflow-hidden">
+      <div className="bg-surface border border-slate-800 rounded-[2.5rem] p-4 md:p-6 max-w-sm w-full shadow-2xl space-y-3 md:space-y-4 animate-in zoom-in-95 duration-300 relative overflow-hidden">
         
         <div className="text-center space-y-3">
           <div className="w-20 h-20 bg-primary/10 text-primary rounded-[2rem] flex items-center justify-center mx-auto mb-6 border border-primary/20 shadow-xl shadow-primary/5">