refactor: architecture compliance pass — DS tokens, hook boundary, god component split, AI hardening

- DS token migration: Anfragen.tsx + child components (AnfragenInquiryItem, AnfragenMessageBubble)
  fully migrated; DS_TEXT.brandDark added; scoreTheme.ts moved to src/lib/ with re-export proxy
- Hook boundary: Results.tsx no longer calls needService directly — routes through useNeeds()
  with optional refetchOnMount/gcTime overrides
- NewListing.tsx (440L) split into useNewListingForm hook + 8 section components under
  src/components/new-listing/; page shell reduced to 121 lines
- AI hardening: Zod .strict() on all schemas, AIProvenance extended with schemaVersion/
  fallbackReason/traceId/latencyMs, AITraceStore stats with p50/p90/p99 + failure breakdowns,
  MockAIService buildFollowUpQuestions with priority ordering + area-ambiguity detection,
  prompt templates updated (LIGHT_INDUSTRIAL, budget unit, ambiguity detection, decimal precision)
- Tests: all 154 passing; fixed test regression caused by OfferEmailResponseSchema body min(50)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/new-listing/index.ts

@@ -0,0 +1,8 @@
+export { AiAssistCard } from './AiAssistCard'
+export { AreaDetailsSection } from './AreaDetailsSection'
+export { AddressSection } from './AddressSection'
+export { SoftFactorsSection } from './SoftFactorsSection'
+export { TechnicalDetailsSection } from './TechnicalDetailsSection'
+export { ImageUrlSection } from './ImageUrlSection'
+export { ContactSection } from './ContactSection'
+export { CreatedScreen } from './CreatedScreen'