fix migration

server/src/db/migration/0008_backfillMonitorLastEvaluatedAt.ts

@@ -3,6 +3,8 @@ import { logger } from "@/utils/logger.js";
 
 /**
  * Backfill lastEvaluatedAt on monitors created before the lastEvaluatedAt existed.
+ *
+ * Stamp the upgrade moment, not 0. If set to 0, all checks will be replayed
  */
 export async function backfillMonitorLastEvaluatedAt(): Promise<void> {
 	const SERVICE_NAME = "Migration:BackfillMonitorLastEvaluatedAt";
@@ -10,7 +12,7 @@ export async function backfillMonitorLastEvaluatedAt(): Promise<void> {
 	try {
 		logger.info({ service: SERVICE_NAME, message: "Starting lastEvaluatedAt backfill" });
 
-		const result = await MonitorModel.updateMany({ lastEvaluatedAt: { $exists: false } }, { $set: { lastEvaluatedAt: 0 } });
+		const result = await MonitorModel.updateMany({ lastEvaluatedAt: { $exists: false } }, { $set: { lastEvaluatedAt: Date.now() } });
 
 		logger.info({
 			service: SERVICE_NAME,