feat: add cancellable document status (#2992)

Adds a CANCELLED envelope status that privileged members (owner or team
admin/manager) can move a pending document into. Sending recipient
notifications via a background job while retaining the document in the
dashboard as proof of distribution.

Includes a dedicated Cancelled tab, single and bulk cancel actions,
the ENVELOPE_CANCELLED mutability guard, and e2e coverage for
permissions
and visibility.

packages/api/v1/implementation.ts

@@ -1,7 +1,7 @@
 import { getServerLimits } from '@documenso/ee/server-only/limits/server';
 import { NEXT_PUBLIC_WEBAPP_URL } from '@documenso/lib/constants/app';
 import { DATE_FORMATS, DEFAULT_DOCUMENT_DATE_FORMAT } from '@documenso/lib/constants/date-formats';
-import { DocumentDataType, EnvelopeType, SigningStatus } from '@prisma/client';
+import { DocumentDataType, DocumentStatus, EnvelopeType, SigningStatus } from '@prisma/client';
 import { tsr } from '@ts-rest/serverless/fetch';
 import { match } from 'ts-pattern';
 import '@documenso/lib/constants/time-zones';
@@ -240,7 +240,12 @@ export const ApiContractV1Implementation = tsr.router(ApiContractV1, {
         };
       }
 
-      if (!downloadOriginalDocument && !isDocumentCompleted(envelope.status)) {
+      // A cancelled document was never sealed, so its data is the unsigned original.
+      // Treat it as not-completed here so a "signed" version is never served for it.
+      // REJECTED and COMPLETED keep their prior behavior.
+      const hasSignedArtifact = isDocumentCompleted(envelope.status) && envelope.status !== DocumentStatus.CANCELLED;
+
+      if (!downloadOriginalDocument && !hasSignedArtifact) {
         return {
           status: 400,
           body: {