When signing a document the final signer is often
greeted with a super long completing spinner since
we are synchronously signing the document and sending
emails to all recipients. This is frustrating and
has caused issues for customers and self-hosters.
Moving sealing to a background job resolves this
and improves the overall snappiness of the app while
also supporting retrying the sealing if it were to
fail in the future.
This has the implication of a document no longer
immediately being in a "completed" state once all
signers have signed. To assist with this we now
refetch the page every 5 seconds upon signing
completion until the document status as shifted to
completed.
Improves the sealing process by being strict on how
long certificate generation can take, opting to fail
generation and continue sealing.
Also changes the ordering of sealing so an error in the
process won't also cause a document to be "COMPLETED"
since it hasn't been cryptographically sealed yet.
The downside to this change is that documents that fail
during sealing will require manual intervention as a signer
or owner won't be able to *complete* the document.
