## Description
Add envelopes V2 embedded support
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Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
API users were inadvertently sending documents without signature fields,
causing confusion for recipients and breaking their signing flows.
- Add getRecipientsWithMissingFields helper in recipients.ts
- Add server-side validation in sendDocument to block distribution
- Fix v1 API to return 400 instead of 500 for validation errors
- Consolidate UI signature field checks to use isSignatureFieldType
- Add E2E tests for both v1 and v2 APIs
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
Konrad