feat: steppable aggr fn

poc: step aggr query

feat: mvp poc stuff

test: sqlness

chore: import missing

feat: support first/last_value

fix: check also include first/last value

tests/cases/distributed/explain/step_aggr.sql

@@ -0,0 +1,144 @@
+CREATE TABLE integers(
+    host STRING,
+    i BIGINT,
+    ts TIMESTAMP TIME INDEX
+) PARTITION ON COLUMNS (host) (
+    host < '550-A',
+    host >= '550-A'
+    AND host < '550-W',
+    host >= '550-W'
+);
+
+INSERT INTO integers (host, i, ts) VALUES
+    ('550-A', 1, '2023-01-01 00:00:00'),
+    ('550-A', 2, '2023-01-01 01:00:00'),
+    ('550-W', 3, '2023-01-01 02:00:00'),
+    ('550-W', 4, '2023-01-01 03:00:00');
+
+-- count
+EXPLAIN SELECT
+    count(i)
+FROM
+    integers;
+
+EXPLAIN SELECT
+    ts,
+    count(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+EXPLAIN SELECT
+    count(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+-- sum
+EXPLAIN SELECT
+    sum(i)
+FROM
+    integers;
+
+EXPLAIN SELECT
+    ts,
+    sum(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+EXPLAIN SELECT
+    sum(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+-- min
+EXPLAIN SELECT
+    min(i)
+FROM
+    integers;
+
+EXPLAIN SELECT
+    ts,
+    min(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+EXPLAIN SELECT
+    min(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+-- max
+EXPLAIN SELECT
+    max(i)
+FROM
+    integers;
+
+EXPLAIN SELECT
+    ts,
+    max(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+EXPLAIN SELECT
+    max(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+-- uddsketch_state
+EXPLAIN SELECT
+    uddsketch_state(128, 0.01, i)
+FROM
+    integers;
+
+EXPLAIN SELECT
+    ts,
+    uddsketch_state(128, 0.01, i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+EXPLAIN SELECT
+    uddsketch_state(128, 0.01, i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+-- hll
+EXPLAIN SELECT
+    hll(i)
+FROM
+    integers;
+
+EXPLAIN SELECT
+    ts,
+    hll(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+EXPLAIN SELECT
+    hll(i)
+FROM
+    integers
+GROUP BY
+    ts;
+
+DROP TABLE integers;