Make reconciliation transaction in async executor

A feature request for async job executor for reconciliation when a page is submitted for a content reconciliation. This would allow us to have merge multiple calls to reconciliation if they are for same content and result in eventual consistency.
Currently, reconciliation runs as a post-commit task for a attachment CRUD operation in a listener and when a lot of linked pages are there to a container of the attachment, it could require a lot of Synchrony recons, which turns into a big transaction in the listener. 
So, it would be great to either:

• Break the reconciliation into multiple transaction, and/or
• Perform this reconciliation with a worker pool in async manner rather than keeping the attachment request blocked.

Customers with the following warning message in their logs will benefit from this request:

WARN [https-jsse-nio2-443-exec-7] [confluence.util.profiling.DurationThresholdWarningTimingHelperFactory] logMessage Execution time for post-commit task com.atlassian.confluence.internal.content.collab.AttachmentRelatedContentReconciliationListener$$Lambda$2945/0x00000001033df040@42a5575b took 148279 ms (warning threshold is 5000 ms)

Impact on apps

ConfiForms - Data Forms & Workflows
The ConfiForms app is affected by the lack of this feature. In particular, a timeout might occur when submitting a form via the app when the forms are configured to move attachments between pages.

Workaround

Reducing the number of items (linked pages or attachment) that are processed as part of the reconciliation request will help preventing this in the first place.