- pg_backup.sh: use the db service's POSTGRES_USER (default postgres) for the
dump/drop/recreate instead of detecting the superuser at runtime, since the
recipe now sets that env var; one-line the constants comment
- release note: explain the in-place pg_upgrade + the POSTGRES_USER override
- bump PG_BACKUP_VERSION v4
Verified on cctest: backup + restore via the hooks round-trips with POSTGRES_USER.
Replaces the paywalled bitnamilegacy app with the official discourse/discourse
image behind Traefik. DB is reused as-is; uploads migrate from the legacy
bitnami volume idempotently. The wrapper entrypoint injects the db_password and
smtp_password secrets (the official image has no *_FILE support). SMTP env vars
are renamed to the official names; release notes cover the migration.
Recipe 0.8.1+3.5.0 -> 1.0.0+3.5.3 (major: new image, env/volume/port changes).
