fix: enhance collaborator access check in DocumentSchema

- Updated the collaborator access check in the DocumentSchema to ensure that a user must have both writable and readable permissions to access a document.
- Improved error handling by providing a more precise condition for user access, enhancing security and clarity in document collaboration.

src/Document/document.schema.ts

@@ -402,7 +402,7 @@ export class DocumentSchema extends PothosSchema {
           if (!document.isPublic) {
             if (
               document.ownerId !== ctx.websocket?.me?.id &&
-              !document.collaborators.some((c) => c.userId === ctx.websocket?.me?.id && c.writable)
+              !document.collaborators.some((c) => c.userId === ctx.websocket?.me?.id && c.writable && c.readable)
             )
               throw new Error('User is not owner or collaborator of document')
           }