feat: 新增前沿信号聚合页面与Webhook入库能力

prisma/schema.prisma

@@ -100,6 +100,31 @@ model Tag {
   @@map("tags")
 }
 
+model Signal {
+  id          String   @id @default(cuid())
+  source      String
+  sourceUrl   String
+  title       String
+  titleEn     String?
+  summary     String
+  summaryEn   String?
+  topic       String?
+  topicEn     String?
+  tags        Json
+  sections    Json
+  engagement  Int      @default(0)
+  publishedAt DateTime
+  isActive    Boolean  @default(true)
+  createdAt   DateTime @default(now())
+  updatedAt   DateTime @updatedAt
+
+  @@unique([source, sourceUrl], map: "uniq_signal_source_url")
+  @@index([source, publishedAt], map: "idx_signal_source_published")
+  @@index([isActive, publishedAt], map: "idx_signal_active_published")
+  @@index([engagement], map: "idx_signal_engagement")
+  @@map("signals")
+}
+
 enum LinkType {
   WEBSITE
   GITHUB