fix(contribution): 将未分配算力汇总到总部账户(HEADQUARTERS)

之前 HEADQUARTERS 账户在算力分配时被遗漏，未获得未分配算力的汇总。
现在在保存未分配算力时，同时更新 HEADQUARTERS 账户的 contributionBalance，
并发布同步事件用于 mining-admin-service 同步。

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

backend/services/contribution-service/src/application/services/contribution-calculation.service.ts

@@ -9,6 +9,7 @@ import { OutboxRepository } from '../../infrastructure/persistence/repositories/
 import { UnitOfWork } from '../../infrastructure/persistence/unit-of-work/unit-of-work';
 import { ContributionAccountAggregate, ContributionSourceType } from '../../domain/aggregates/contribution-account.aggregate';
 import { ContributionRecordAggregate } from '../../domain/aggregates/contribution-record.aggregate';
+import { ContributionAmount } from '../../domain/value-objects/contribution-amount.vo';
 import { SyncedReferral } from '../../domain/repositories/synced-data.repository.interface';
 import { ContributionDistributionPublisherService } from './contribution-distribution-publisher.service';
 import { ContributionRateService } from './contribution-rate.service';
@@ -279,6 +280,30 @@ export class ContributionCalculationService {
         })),
       );
 
+      // 汇总未分配算力到 HEADQUARTERS（总部账户）
+      const totalUnallocatedAmount = result.unallocatedContributions.reduce(
+        (sum, u) => sum.add(u.amount),
+        new ContributionAmount(0),
+      );
+      await this.systemAccountRepository.addContribution('HEADQUARTERS', totalUnallocatedAmount);
+
+      // 发布 HEADQUARTERS 账户同步事件
+      const headquartersAccount = await this.systemAccountRepository.findByType('HEADQUARTERS');
+      if (headquartersAccount) {
+        const hqEvent = new SystemAccountSyncedEvent(
+          'HEADQUARTERS',
+          headquartersAccount.name,
+          headquartersAccount.contributionBalance.value.toString(),
+          headquartersAccount.createdAt,
+        );
+        await this.outboxRepository.save({
+          aggregateType: SystemAccountSyncedEvent.AGGREGATE_TYPE,
+          aggregateId: 'HEADQUARTERS',
+          eventType: SystemAccountSyncedEvent.EVENT_TYPE,
+          payload: hqEvent.toPayload(),
+        });
+      }
+
       // 发布未分配算力同步事件（用于 mining-service 同步待解锁算力）
       for (const unallocated of result.unallocatedContributions) {
         const event = new UnallocatedContributionSyncedEvent(