DocuSign Integration with SharePoint Framework (SPFx)

planning to integrate DocuSign eSignature with a SharePoint Framework (SPFx) web part.

Requirements

• Users submit requests through a SharePoint Online site.
• Upon submission, a DocuSign envelope should be created automatically and sent to designated recipients for e-signature.
• The organization has a single dedicated DocuSign service account.
• SharePoint users are not DocuSign users and should not be required to log in to DocuSign separately.
• Recipients should receive DocuSign emails directly and complete the signing process through DocuSign.
• The signed document and envelope status should be stored and tracked within SharePoint.
• Due to project constraints, the current approach being considered is calling DocuSign APIs directly from the SPFx web part.

Questions

1. What is the recommended enterprise architecture for this scenario?
2. Can a single DocuSign service account be used to create and send envelopes for all SharePoint users?
3. How should authentication be handled between SharePoint Online, Microsoft Entra ID, SPFx, and DocuSign?
4. Is it technically feasible and secure to call DocuSign APIs directly from the SPFx web part?
5. What are the security, licensing, and compliance considerations of using a shared DocuSign account?
6. How can envelope status updates and signed documents be synchronized back to SharePoint automatically?
7. What are the recommended production deployment practices and design patterns for scalability, security, and maintainability?

I am looking for guidance on designing a scalable, secure, and enterprise-grade DocuSign integration with SharePoint Online, including best practices and potential risks associated with direct API calls from SPFx.