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/pages/demand/MatchDetail.tsx

@@ -88,7 +88,7 @@ export default function MatchDetail() {
   const handleCompare = () => {
     if (match && !isFuture && property) {
       addToCompare({
-        resultType: property.resultType === 'EXTERNAL_MARKET' ? 'EXTERNAL_MARKET' : 'VERIFIED_PORTFOLIO',
+        resultType: property.resultType ?? 'VERIFIED_PORTFOLIO',
         matchId: match.id, needId: match.needId, matchScore: match.matchScore, match, property,
       })
     } else if (match && isFuture && signal) {

src/pages/demand/Results.tsx

@@ -73,7 +73,7 @@ export default function Results() {
   const { platformCount, maisonWorkCount, futureCount, missingDataCount } = useMemo(() => {
     let platform = 0, maison = 0, future = 0, missing = 0
     for (const r of results) {
-      if (r.resultType === 'VERIFIED_PORTFOLIO' || r.resultType === 'EXTERNAL_MARKET') platform++
+      if (r.resultType === 'VERIFIED_PORTFOLIO') platform++
       else if (r.resultType === 'MAISON_WORK') maison++
       else if (r.resultType === 'FUTURE_AVAILABILITY') future++
       if ('match' in r && Array.isArray((r as { match?: { missingData?: unknown[] } }).match?.missingData) &&
@@ -91,7 +91,6 @@ export default function Results() {
         return filterSource === 'ALL' || filterSource === 'PLATFORM'
       }
       if (filterSource === 'ALL') return true
-      if (filterSource === 'PLATFORM') return r.resultType === 'EXTERNAL_MARKET'
       return r.resultType === filterSource
     })
     return sortResults(filtered, sortBy)

src/pages/supply/newListingMapper.ts

@@ -47,7 +47,7 @@ export function buildCreatePropertyInput(fields: {
   return {
     title: `${ASSET_TYPE_LABELS[assetType] ?? assetType} · ${city}`,
     assetType: assetType as typeof AssetType[keyof typeof AssetType],
-    resultType: ResultType.EXTERNAL_MARKET,
+    resultType: ResultType.VERIFIED_PORTFOLIO,
     sourceType: 'DIRECT',
     location: { city, country: 'CH' },
     address: {