test(11-05): add failing TenderTriageService spec + TenderTriage schema/migration

RED phase (TDD) for UI-03/04 per-user triage (gelesen/ungelesen, Favorit).
Adds the TenderTriage Prisma model (userId-scoped, onDelete: Cascade to
Tender per Pitfall 6) and its migration, plus a failing spec proving
upsert idempotency, strict userId scoping (V4/IDOR, T-11-10), and cascade
consistency — service implementation follows in the GREEN commit.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/api/prisma/schema.prisma

@@ -290,6 +290,30 @@ model Tender {
   @@index([bundesland]) // FILTER-02: post-backfill Bundesland-Filter-Performance
   @@index([cpvDivisions], type: Gin) // FILTER-03: post-backfill CPV-Divisions-Filter-Performance (hasSome)
   // Deliberately NO tenant column and NO tenant index — this is global data (D-03)
+  triage TenderTriage[]
+}
+
+// UI-03/04 — per-user Triage-Zustand pro Tender (gelesen/ungelesen, Favorit).
+// Scoping-Muster wie FavoriteLink (T-08-06, Pitfall 4): userId-Scoping im
+// Service, KEIN forTenant()/RLS — RLS existiert nur für Auth-Kerntabellen.
+// tenantId wird zusätzlich mitgeführt (spätere Tenant-Isolation, T-11-12),
+// ist aber NICHT das Scoping-Feld — jede Query filtert auf userId.
+model TenderTriage {
+  id          String    @id @default(uuid())
+  userId      String
+  tenantId    String
+  tenderId    String
+  isRead      Boolean   @default(false)
+  isFavorite  Boolean   @default(false)
+  readAt      DateTime?
+  favoritedAt DateTime?
+  createdAt   DateTime  @default(now())
+  updatedAt   DateTime  @updatedAt
+  tender      Tender    @relation(fields: [tenderId], references: [id], onDelete: Cascade)
+
+  @@unique([userId, tenderId]) // Upsert-Target (setTriage); ein Triage-Row je (user,tender)
+  @@index([userId])
+  @@index([tenderId])
 }
 
 // Singleton-per-source admin poll config (INGEST-06 foundation).