fix(trading): 合并销毁和快照任务确保K线价格正确

将 executeMinuteBurn 和 createPriceSnapshot 合并为单个 cron 任务，
确保快照在销毁完成后创建，避免K线出现价格不变的间隔

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

backend/services/trading-service/src/application/schedulers/burn.scheduler.ts

@@ -27,30 +27,25 @@ export class BurnScheduler implements OnModuleInit {
   }
 
   /**
-   * 每分钟执行销毁
+   * 每分钟执行销毁并创建价格快照
    * 每分钟销毁量 = 100亿 ÷ (365×4×1440) = 4756.468797564687 进黑洞
+   *
+   * 注意：销毁和快照必须在同一个任务中顺序执行，
+   * 确保快照总是捕获销毁后的最新价格，避免K线出现价格不变的情况
    */
   @Cron(CronExpression.EVERY_MINUTE)
-  async executeMinuteBurn(): Promise<void> {
+  async executeMinuteBurnAndSnapshot(): Promise<void> {
     try {
+      // 1. 先执行销毁
       const burnAmount = await this.burnService.executeMinuteBurn();
       if (!burnAmount.isZero()) {
         this.logger.debug(`Minute burn completed: ${burnAmount.toFixed(8)}`);
       }
-    } catch (error) {
-      this.logger.error('Failed to execute minute burn', error);
-    }
-  }
 
-  /**
-   * 每分钟创建价格快照
-   */
-  @Cron(CronExpression.EVERY_MINUTE)
-  async createPriceSnapshot(): Promise<void> {
-    try {
+      // 2. 销毁完成后立即创建价格快照
       await this.priceService.createSnapshot();
     } catch (error) {
-      this.logger.error('Failed to create price snapshot', error);
+      this.logger.error('Failed to execute minute burn and snapshot', error);
     }
   }