Tasks endpoint

sql/tasks/list.sql

@@ -9,6 +9,6 @@ SELECT
 FROM
     tasks
 WHERE
-    owner = $1
+    owner = $1 AND ($2 IS NULL OR id > $2) AND ($3 IS NULL OR id < $3)
 ORDER BY created_at ASC
-LIMIT $2 OFFSET $3;
+LIMIT $4;