fix(injection): findUnique 改为 findFirst 避免命名唯一索引类型错误

Prisma @@unique 单字段命名索引 uk_adoption_id 的 TypeScript 类型
与 findUnique where 输入不兼容（TS2322）。改用 findFirst + where
字段查询，走同一个唯一索引，性能相同。

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/services/mining-blockchain-service/src/infrastructure/persistence/repositories/adoption-injection-record.repository.impl.ts

@@ -43,8 +43,8 @@ export class AdoptionInjectionRecordRepositoryImpl implements IAdoptionInjection
   }
 
   async findByAdoptionId(adoptionId: string): Promise<AdoptionInjectionRecordDto | null> {
-    const record = await this.prisma.adoptionInjectionRecord.findUnique({
+    const record = await this.prisma.adoptionInjectionRecord.findFirst({
-      where: { uk_adoption_id: { adoptionId } },
+      where: { adoptionId },
     });
     return record ? this.mapToDto(record) : null;
   }