Feature: Need a purge mechanism to clean up the very old reports on OpenSearch and ElasticSearch

[JingChen23]

The report list has a limit, which is good. However, the total number on the right-bottom will keep increasing, indefinitely. Actully the very old reports means little, so we need a mechanism to purse those stuffs on OS or ES, to avoid crashing them.

A good proposal is: add a limit setting, and use the number to purse the old reports.

[4everming]

An option is to create indices in opensearch/elasticsearch by day and use a unified alias to reference all the indices. After that, indices out-of-date can be removed from the reference background periodically without the awareness of the front end or any downtime. Refer to: https://opensearch.org/docs/latest/api-reference/alias/