fix: Update staffDocument mutation file

backend/dataconnect/connector/staffDocument/mutations.gql

@@ -31,6 +31,42 @@ mutation updateStaffDocument(
     data: {
       status: $status
       documentUrl: $documentUrl
+      expiryDate: $expiryDate
+    }
+  ) 
+}
+
+# ------------------------------------------------------------
+# UPSERT STAFF DOCUMENT
+# Creates the document record if it does not exist, or updates
+# it if it already exists (matched by staffId + documentId key).
+# Use this when uploading a document for the first time or
+# re-uploading/updating an existing one.
+#
+# To update multiple documents in a single network call, use
+# aliased mutations in one GraphQL request from the client:
+#
+# mutation {
+#   doc1: upsertStaffDocument(staffId: $id, staffName: $name, documentId: $d1, ...)
+#   doc2: upsertStaffDocument(staffId: $id, staffName: $name, documentId: $d2, ...)
+# }
+# ------------------------------------------------------------
+mutation upsertStaffDocument(
+  $staffId: UUID!
+  $staffName: String!
+  $documentId: UUID!
+  $status: DocumentStatus!
+  $documentUrl: String
+  $expiryDate: Timestamp
+) @auth(level: USER) {
+  staffDocument_upsert(
+    data: {
+      staffId: $staffId
+      staffName: $staffName
+      documentId: $documentId
+      status: $status
+      documentUrl: $documentUrl
+      expiryDate: $expiryDate
     }
   )
 }