feat: add task sorting & filtering

adds filtering by task status (completion date, incomplete, completion)
adds filtering by task metadata (task name, labels, members, due date)
adds sorting by task name, labels, members, and due date

frontend/src/shared/graphql/fragments/task.ts

@@ -7,6 +7,7 @@ const TASK_FRAGMENT = gql`
     description
     dueDate
     complete
+    completedAt
     position
     badges {
       checklist {