feat: mix Schattenmarkt into result tiers, add filter toggle

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

src/pages/demand/Results.tsx

@@ -16,7 +16,7 @@ import { AddToShortlistDialog } from '../../components/shortlist'
 import type { ResultType } from '../../domain/enums'
 import type { UnifiedMatchResult } from '../../domain/unifiedResult'
 
-type FilterSource = ResultType | 'ALL'
+type FilterSource = Exclude<ResultType, 'FUTURE_AVAILABILITY'> | 'ALL'
 type SortBy = 'score' | 'rent' | 'area'
 
 function sortResults(results: UnifiedMatchResult[], sortBy: SortBy): UnifiedMatchResult[] {
@@ -36,6 +36,7 @@ export default function Results() {
   const queryClient = useQueryClient()
   const [filterSource, setFilterSource] = useState<FilterSource>('ALL')
   const [sortBy, setSortBy] = useState<SortBy>('score')
+  const [showSchattenmarkt, setShowSchattenmarkt] = useState(true)
   const [view, setView] = useState<'list' | 'grid'>(() =>
     (localStorage.getItem('view-results') as 'list' | 'grid') ?? 'list'
   )
@@ -67,8 +68,9 @@ export default function Results() {
 
   const { data: results = [], isLoading } = useUnifiedResults(activeNeed?.id)
 
-  const filtered =
-    filterSource === 'ALL' ? results : results.filter(r => r.resultType === filterSource)
+  const filtered = results
+    .filter(r => filterSource === 'ALL' || r.resultType === filterSource)
+    .filter(r => showSchattenmarkt || r.resultType !== 'FUTURE_AVAILABILITY')
 
   const sorted = sortResults(filtered, sortBy)
 
@@ -167,12 +169,14 @@ export default function Results() {
           onFilterChange={setFilterSource}
           sortBy={sortBy}
           onSortChange={setSortBy}
+          showSchattenmarkt={showSchattenmarkt}
+          onShowSchattenmarktChange={setShowSchattenmarkt}
         />
 
         {isLoading ? (
           <FeedSkeleton />
         ) : sorted.length === 0 ? (
-          <FeedEmptyState filtered={filterSource !== 'ALL'} />
+          <FeedEmptyState filtered={filterSource !== 'ALL' || !showSchattenmarkt} />
         ) : (
           <UnifiedResultFeed results={sorted} view={view} />
         )}