feat: remove EXTERNAL_MARKET result type entirely

All external market properties now surface as VERIFIED_PORTFOLIO.
Removes the type from enums, domain types, mock data, matching engine,
components, hooks, and tests — zero user-visible distinction remains.

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

src/components/match-card/MatchCardCompareMini.tsx

@@ -5,7 +5,6 @@ import type { MatchCardViewModel } from './MatchCardViewModel'
 
 const RESULT_TYPE_META: Record<string, { label: string; color: string }> = {
   VERIFIED_PORTFOLIO:  { label: 'Verified',    color: '#1e3a5f' },
-  EXTERNAL_MARKET:     { label: 'Direkt',      color: '#d97706' },
   MAISON_WORK:         { label: 'Maison Work', color: '#0369a1' },
   FUTURE_AVAILABILITY: { label: 'Signal',      color: '#7c3aed' },
 }