feat(jobs): 增加后台任务运行时

apps/server/prisma/schema.prisma

@@ -423,6 +423,25 @@ model AiLog {
   @@map("ai_logs")
 }
 
+model BackgroundJob {
+  id          String   @id @default(cuid())
+  type        String
+  status      String   @default("queued")
+  dedupeKey   String?  @map("dedupe_key")
+  payload     Json     @default("{}")
+  attempts    Int      @default(0)
+  maxAttempts Int      @default(3) @map("max_attempts")
+  availableAt DateTime @default(now()) @map("available_at")
+  lockedBy    String?  @map("locked_by")
+  lockedUntil DateTime? @map("locked_until")
+  lastError   String?  @map("last_error")
+  completedAt DateTime? @map("completed_at")
+  createdAt   DateTime @default(now()) @map("created_at")
+  updatedAt   DateTime @updatedAt @map("updated_at")
+
+  @@map("background_jobs")
+}
+
 model XiaobaoRiskSummary {
   versionId           String   @id @map("version_id")
   riskLevel           String   @map("risk_level")