feat: add removeCollaborator mutation to DocumentSchema

- Introduced a new mutation to allow document owners to remove collaborators from a document.
- Implemented authorization checks to ensure only the document owner can perform this action.
- Enhanced error handling for cases where the document is not found or the user is not the owner.

src/Document/document.schema.ts

@@ -333,6 +333,25 @@ export class DocumentSchema extends PothosSchema {
           })
         },
       }),
+      removeCollaborator: t.prismaField({
+        type: this.documentCollaborator(),
+        args: {
+          documentId: t.arg({ type: 'String', required: true }),
+          userId: t.arg({ type: 'String', required: true }),
+        },
+        resolve: async (_, __, args, ctx: SchemaContext) => {
+          if (ctx.isSubscription) throw new Error('Not allowed')
+          // check if ctx user is owner of document
+          const document = await this.prisma.document.findUnique({
+            where: { id: args.documentId },
+          })
+          if (!document) throw new Error('Document not found')
+          if (document.ownerId !== ctx.http?.me?.id) throw new Error('User is not owner of document')
+          return await this.prisma.documentCollaborator.delete({
+            where: { documentId_userId: { documentId: args.documentId, userId: args.userId } },
+          })
+        },
+      }),
     }))
 
     this.builder.subscriptionFields((t) => ({