fix: store activity timestamps in UTC

Convert timestamps to UTC before storing to ensure consistent timezone
handling. Previously local time was stored without timezone marker,
causing times to appear in the future when displayed.

Author: daviddao

internal/database/repositories/jetstream_activity.go

@@ -58,17 +58,20 @@ func (r *JetstreamActivityRepository) LogActivityWithStatus(
 	var sqlStr string
 	var timestampStr string
 
+	// Always store in UTC for consistency
+	utcTime := timestamp.UTC()
+
 	switch r.db.Dialect() {
 	case database.PostgreSQL:
-		timestampStr = timestamp.Format(time.RFC3339)
+		timestampStr = utcTime.Format(time.RFC3339)
 		sqlStr = fmt.Sprintf(`INSERT INTO jetstream_activity 
 			(timestamp, operation, collection, did, status, event_json)
 			VALUES (%s, %s, %s, %s, %s, %s)
 			RETURNING id`,
 			r.db.Placeholder(1), r.db.Placeholder(2), r.db.Placeholder(3),
 			r.db.Placeholder(4), r.db.Placeholder(5), r.db.Placeholder(6))
 	default:
-		timestampStr = timestamp.Format("2006-01-02 15:04:05")
+		timestampStr = utcTime.Format("2006-01-02 15:04:05")
 		sqlStr = fmt.Sprintf(`INSERT INTO jetstream_activity 
 			(timestamp, operation, collection, did, status, event_json)
 			VALUES (%s, %s, %s, %s, %s, %s)`,