Auto-{compact, cleanup, re-index}

[wjones127]

We might want to support some limited automatic table maintenance to make things easier for users.

However, this is difficult to do if there are concurrent writers. We could allow enabling a configuration on the table that will do automatic maintenance, but only if the user promises there is only 1 writer. We could then have conditions after a write happens to check whether we want to do one or more of the maintenance operations.

• Simple auto cleanup #2100
• Auto compaction / reindexing