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

migrations/0051_add-completed_at-to-task-table.up.sql

@@ -0,0 +1,4 @@
+ALTER TABLE task ADD COLUMN completed_at timestamptz;
+UPDATE task as t1 SET completed_at = NOW()
+  FROM task as t2
+  WHERE t1.task_id = t2.task_id AND t1.complete = true;