### Summary
- Add Cache-Control headers to all route responses (1h s-maxage, 2h
stale-while-revalidate)
- Append current month to chart data so graphs stay up-to-date
(cumulative carries forward, else zero)
- Remove `.limit(12)` from growth queries for full history
- Pass isCumulative flag through addZeroMonth
- Deduplicate TransformedData type, remove transformRepoStats
This PR is handles the changes required to support envelopes. The new
envelope editor/signing page will be hidden during release.
The core changes here is to migrate the documents and templates model to
a centralized envelopes model.
Even though Documents and Templates are removed, from the user
perspective they will still exist as we remap envelopes to documents and
templates.
Lucas Smith
David Nguyen
Ephraim Duncan
Vincent Vu
Dunsin