[DmitriiAn]

Problem

Cloning from a PG 17 or 18 source dies at the schema-dump step:

pg_dump: error: aborting because of server version mismatch
pg_dump: detail: server version: 17.11; pg_dump version: 16.14

Fix

Default PGVERSION to 18 in both Dockerfile stages, and in the root Makefile so make build matches what we publish. A single newest client is sufficient: pg_dump 18 reads servers back to 9.2, covering everything pgcopydb supports. pg_dump/pg_restore continue to resolve through the standard postgresql-common wrapper at /usr/bin, exactly as they do today — no PATH changes, no new packages, no source changes.

[teknogeek0]

Closing in favor of #65, which makes the same change to Dockerfile and Makefile and also covers the test side: the source database in 12 suites now follows PGVERSION through a compose build arg, the follow-wal2json and follow-target-reconnect source image tags follow PGVERSION so one version cannot reuse another version's image, and exclude-extension no longer hardcodes pgcopydb:pg16.

Thanks for finding the pg_dump version mismatch — #65 carries that reason into the v0.20 changelog.