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Summary

Databend Internal Storage FuseTable is similar to Apache Iceberg, which is a Log Structured Table and need to compact/recluster/vacuum table regularly to merge small data chunks, sort them by the cluster key or vacuum unneeded branches.

Previously, those implementation rely on different drivers which add some complexity for infrastructure as we need to deploy and maintain additional service to trigger driver events.
Thus we need to introduce the Background Service, which allow to run databend as a background one-shot job or as a background daemon to run cron jobs,
jobs may trigger table maintainence tasks, for example, automatic compaction/vacuum/recluster by cron based/ critiria based without additional maintainence needed

This implementation contain:

1. complete metasrv schema definition and background_job and background_tasks
2. apis to update and maintain background_job and background_task state on meta-service
3. simplified job scheduler implementation which support one_shot, interval, cron job type.

Not contain:

1. cron job graceful shutdown
2. tests on background job state machine
3. management apis or call procedures to view and create background jobs by user
4. Cluster mode background service, as we need a leader election process to ensure a leader to initialize requests

Closes #issue