fix(mining-admin-service): properly handle Debezium outbox CDC events

- Add isDebeziumOutboxEvent to detect outbox table CDC messages
- Add handleDebeziumOutboxEvent to extract service event from payload.after
- Fix CDC consumer not recognizing events from contribution-service outbox

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

backend/services/mining-admin-service/src/infrastructure/kafka/cdc-consumer.service.ts

@@ -176,11 +176,19 @@ export class CdcConsumerService implements OnModuleInit, OnModuleDestroy {
 
       // 判断事件类型：Debezium CDC 或 服务 Outbox 事件
       if (this.isDebeziumEvent(eventData)) {
-        await this.handleCdcEvent(topic, eventData, sequenceNum);
+        // Debezium outbox 事件：从 payload.after 提取服务事件
+        if (this.isDebeziumOutboxEvent(eventData)) {
+          await this.handleDebeziumOutboxEvent(topic, eventData, sequenceNum);
+        } else {
+          // 普通 Debezium CDC 事件（表变更）
+          await this.handleCdcEvent(topic, eventData, sequenceNum);
+        }
       } else if (this.isServiceEvent(eventData)) {
+        // 直接发布的服务事件（非 Debezium）
         await this.handleServiceEvent(topic, eventData, sequenceNum);
       } else {
         this.logger.warn(`Unknown event format from topic: ${topic}`);
+        this.logger.debug(`Event data: ${JSON.stringify(eventData).substring(0, 500)}`);
       }
     } catch (error) {
       this.logger.error(
@@ -194,6 +202,17 @@ export class CdcConsumerService implements OnModuleInit, OnModuleDestroy {
     return data.payload && data.payload.source && data.payload.op;
   }
 
+  /**
+   * 判断是否为 Debezium outbox 事件
+   * Debezium 监听 outbox_events 表产生的 CDC 消息
+   */
+  private isDebeziumOutboxEvent(data: any): boolean {
+    const after = data.payload?.after;
+    if (!after) return false;
+    // outbox 表有 event_type 字段
+    return after.event_type && after.aggregate_type;
+  }
+
   private isServiceEvent(data: any): boolean {
     // 支持两种格式：
     // 1. 驼峰格式 (服务直接发布): eventType, aggregateType
@@ -202,6 +221,25 @@ export class CdcConsumerService implements OnModuleInit, OnModuleDestroy {
            (data.event_type && data.aggregate_type);
   }
 
+  /**
+   * 处理 Debezium outbox 事件
+   * 从 payload.after 提取服务事件并处理
+   */
+  private async handleDebeziumOutboxEvent(
+    topic: string,
+    eventData: any,
+    sequenceNum: bigint,
+  ): Promise<void> {
+    const op = eventData.payload.op;
+    // 只处理 create 操作（新增的 outbox 记录）
+    if (op !== 'c' && op !== 'r') {
+      return;
+    }
+
+    const after = eventData.payload.after;
+    await this.handleServiceEvent(topic, after, sequenceNum);
+  }
+
   private async handleCdcEvent(
     topic: string,
     eventData: any,