pgsql: Tighten up tsqueryrecv().

Tighten up tsqueryrecv().

tsqueryrecv() accepted zero-length lexemes, which tsqueryin() doesn't.
It also accepted phrase distance values larger than MAXENTRYPOS,
which tsqueryin() doesn't. While neither of these omissions are
very harmful in themselves, they do allow accepting tsquery values
that will fail in a subsequent textual dump/reload.

Commit 23d9ad771 performed similar tightening of tsvectorrecv(),
but I left off these changes at the time because they didn't seem
to have security implications.

Reported-by: Claude Code (via Noah Misch)
Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Discussion: https://postgr.es/m/455079.1786897319@sss.pgh.pa.us
Backpatch-through: 14

Branch
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REL_19_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/1c732c8518d88c2663f96236bf8bb104f3d0a5d4

Modified Files
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src/backend/utils/adt/tsquery.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)