JSON->text plan translation issues

Goal & TODO

Fix known issues with JSON->text translation for EXPLAIN (ANALYZE, BUFFERS) plans:

• Joe shows Subquery Scan (cost=... instead of Subquery Scan on "*SELECT*" (cost=...
• Joe shows Merge Join (cost=... instead of Merge Anti Join (cost=
• Joe shows Values Scan instead of Values Scan on "*VALUES*_1"
• Joe shows Function Scan ... instead of Function Scan on unnest u1 ...
• Joe shows Nested Loop Join ... instead of Nested Loop Hash Join ...
• Joe misses Merge Cond: ...
• Joe misses Function Name ..

Details: slack thread (internal)

Acceptance criteria

Joe's "plan with execution" for the query discussed in slack thread (internal) is identical to that one we have when running EXPLAIN (BUFFERS, ANALYZE) in psql manually (disregarding timing values).