[CrazyBoy49z]

Behavior

• Authenticated 404 and 403 use the actual Lazy Admin header, navigation, theme and layout, with a compact two-column admin-style error panel.
• Guest requests and 401/419/429/500/503 use the standalone fallback so the error page doesn't rely on a broken session or UI dependencies.
• JSON/Livewire and public routes retain the existing exception handling behavior.
• Add coverage for guest fallback and authenticated 404.

All changes in one commit. Tests and authenticated visual QA are pending.