BUG #18778: Query planning fails in ExecInitExprRec with unrecognized node type

The following bug has been logged on the website:

Bug reference:      18778
Logged by:          Alexander Lakhin
Email address:      exclusion@gmail.com
PostgreSQL version: 17.2
Operating system:   Ubuntu 24.04
Description:        

The following script:
CREATE TABLE t (id int, PRIMARY KEY (id)) PARTITION BY RANGE (id);
CREATE TABLE t0 PARTITION OF t FOR VALUES FROM (0) TO (1);
CREATE TABLE t1 PARTITION OF t FOR VALUES FROM (1) TO (2);

SELECT 1 FROM (SELECT EXISTS (SELECT 1 FROM t0 WHERE id = t00.id) AS b FROM
t0 t00) r, t
WHERE t.id > CASE WHEN jsonb_build_object(b) IS NULL THEN 1 ELSE 1 END;

fails with:
ERROR:  XX000: unrecognized node type: 24
LOCATION:  ExecInitExprRec, execExpr.c:2657

The first bad commit for this anomaly (discovered with SQLsmith) is
41efb8340.