Consolidate document draft management into updateDocument

Replace the three separate draft mutations (createDraftDocumentVersion,
updateDocumentVersion, deleteDraftDocumentVersion) with automatic draft
lifecycle management inside updateDocument. The backend now auto-creates
a draft when a published document is edited, updates the existing draft
on subsequent edits, and auto-deletes the draft when content reverts to
match the published version.

A new deleteDocumentDraft mutation provides explicit draft deletion.

Backend:
- Merge version-level fields (content, title, classification,
  documentType) into UpdateDocumentRequest
- Convert CreateDraft, UpdateVersion, DeleteDraft into private
  transaction helpers called from Update
- Update returns (*Document, *DocumentVersion, error) with the version
  present only when a draft exists

Frontend:
- Remove all create/update/delete draft mutations from components
- Auto-save via updateDocument with layout refetch on draft status
  transitions while preserving editor cursor (data-generation key)
- Title, type, and classification editable on published versions
  (backend auto-creates draft)
- Forms use react-hook-form values option to stay synced with Relay
  fragment data across draft/publish transitions

API surface (GraphQL, MCP, CLI, n8n) updated consistently:
- Removed: createDraftDocumentVersion, updateDocumentVersion,
  deleteDraftDocumentVersion
- Added: deleteDocumentDraft (document-level)
- Updated: updateDocument accepts content, classification, documentType

Signed-off-by: Sacha Al Himdani <sacha@getprobo.com>

pkg/server/api/console/v1/schema.graphql

@@ -3892,6 +3892,7 @@ type Mutation {
     # Document mutations
     createDocument(input: CreateDocumentInput!): CreateDocumentPayload!
     updateDocument(input: UpdateDocumentInput!): UpdateDocumentPayload!
+    deleteDocumentDraft(input: DeleteDocumentDraftInput!): DeleteDocumentDraftPayload!
     archiveDocument(input: ArchiveDocumentInput!): ArchiveDocumentPayload!
     unarchiveDocument(input: UnarchiveDocumentInput!): UnarchiveDocumentPayload!
     deleteDocument(input: DeleteDocumentInput!): DeleteDocumentPayload!
@@ -3955,15 +3956,6 @@ type Mutation {
     generateDocumentChangelog(
         input: GenerateDocumentChangelogInput!
     ): GenerateDocumentChangelogPayload!
-    createDraftDocumentVersion(
-        input: CreateDraftDocumentVersionInput!
-    ): CreateDraftDocumentVersionPayload!
-    deleteDraftDocumentVersion(
-        input: DeleteDraftDocumentVersionInput!
-    ): DeleteDraftDocumentVersionPayload!
-    updateDocumentVersion(
-        input: UpdateDocumentVersionInput!
-    ): UpdateDocumentVersionPayload!
     requestSignature(input: RequestSignatureInput!): RequestSignaturePayload!
     bulkRequestSignatures(
         input: BulkRequestSignaturesInput!
@@ -4673,6 +4665,10 @@ input CreateDocumentInput {
 
 input UpdateDocumentInput {
     id: ID!
+    title: String
+    content: String
+    classification: DocumentClassification
+    documentType: DocumentType
     trustCenterVisibility: TrustCenterVisibility
     defaultApproverIds: [ID!]
 }
@@ -4703,6 +4699,10 @@ input ExportTransferImpactAssessmentsPDFInput {
     filter: TransferImpactAssessmentFilter
 }
 
+input DeleteDocumentDraftInput {
+    documentId: ID!
+}
+
 input ArchiveDocumentInput {
     documentId: ID!
 }
@@ -5442,6 +5442,12 @@ type ExportTransferImpactAssessmentsPDFPayload {
 
 type UpdateDocumentPayload {
     document: Document!
+    documentVersion: DocumentVersion
+    documentVersionEdge: DocumentVersionEdge
+}
+
+type DeleteDocumentDraftPayload {
+    document: Document!
 }
 
 type ArchiveDocumentPayload {
@@ -5922,38 +5928,10 @@ type BulkPublishDocumentVersionsPayload {
     documents: [Document!]!
 }
 
-type CreateDraftDocumentVersionPayload {
-    documentVersionEdge: DocumentVersionEdge!
-}
-
-type DeleteDraftDocumentVersionPayload {
-    deletedDocumentVersionId: ID!
-}
-
-input CreateDraftDocumentVersionInput {
-    documentID: ID!
-}
-
-input DeleteDraftDocumentVersionInput {
-    documentVersionId: ID!
-}
-
-input UpdateDocumentVersionInput {
-    documentVersionId: ID!
-    title: String
-    content: String
-    classification: DocumentClassification
-    documentType: DocumentType
-}
-
 input CancelSignatureRequestInput {
     documentVersionSignatureId: ID!
 }
 
-type UpdateDocumentVersionPayload {
-    documentVersion: DocumentVersion!
-}
-
 input SendSigningNotificationsInput {
     organizationId: ID!
 }