fix: 创建知识点时更新知识库 itemCount 计数

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/modules/knowledge-items/knowledge-items.repository.ts

@@ -12,7 +12,7 @@ export class KnowledgeItemsRepository {
     itemType?: string;
     orderIndex?: number;
   }) {
-    return this.prisma.knowledgeItem.create({
+    const item = await this.prisma.knowledgeItem.create({
       data: {
         userId,
         knowledgeBaseId,
@@ -23,6 +23,14 @@ export class KnowledgeItemsRepository {
         orderIndex: dto.orderIndex ?? 0,
       },
     });
+
+    // 更新知识库 itemCount
+    await this.prisma.knowledgeBase.update({
+      where: { id: knowledgeBaseId },
+      data: { itemCount: { increment: 1 } },
+    });
+
+    return item;
   }
 
   async findById(id: string) {