feat(pitch-deck): USP slide redesign + add to sidebar

- USP added to slideNames (DE+EN) and chat display names
- Circular layout: BreakPilot hub center, rotating ring,
  Compliance & Code sections inside circle
- 4 capability cards in corners connected by dashed lines
- Removed variant toggle (kept variant A design)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pitch-deck/app/api/chat/route.ts

@@ -12,6 +12,7 @@ const SLIDE_DISPLAY_NAMES: Record<string, { de: string; en: string }> = {
   'cover': { de: 'Cover', en: 'Cover' },
   'problem': { de: 'Das Problem', en: 'The Problem' },
   'solution': { de: 'Die Lösung', en: 'The Solution' },
+  'usp': { de: 'USP', en: 'USP' },
   'product': { de: 'Produkte', en: 'Products' },
   'how-it-works': { de: 'So funktioniert\'s', en: 'How It Works' },
   'market': { de: 'Markt', en: 'Market' },