fix: finalize weekly postgres backup retention

infra/install-postgres-backup-cron.sh

@@ -2,8 +2,9 @@
 set -eu
 
 temporary=$(mktemp)
+app_dir=$(CDPATH= cd -- "$(dirname "$0")/.." && pwd)
 trap 'rm -f -- "$temporary"' EXIT HUP INT TERM
 
 crontab -l 2>/dev/null | grep -v 'postgres-backup.sh' > "$temporary" || true
-printf '%s\n' '30 3 * * 0 flock -n /tmp/miem-postgres-backup.lock /srv/miem_workers/infra/postgres-backup.sh >/dev/null 2>&1' >> "$temporary"
+printf '%s\n' "30 3 * * 0 flock -n /tmp/miem-postgres-backup.lock $app_dir/infra/postgres-backup.sh >/dev/null 2>&1" >> "$temporary"
 crontab "$temporary"

infra/postgres-backup.sh

@@ -2,8 +2,8 @@
 set -eu
 umask 077
 
-app_dir=/srv/miem_workers
-backup_dir=/home/codex/backups/postgres
+app_dir=$(CDPATH= cd -- "$(dirname "$0")/.." && pwd)
+backup_dir="$HOME/backups/postgres"
 backup="$backup_dir/postgres-latest.sql"
 temporary="$backup.tmp.$$"
 
@@ -14,5 +14,5 @@ cd "$app_dir"
 docker compose exec -T postgres sh -c 'pg_dumpall -U "$POSTGRES_USER"' > "$temporary"
 test -s "$temporary"
 mv "$temporary" "$backup"
-find /home/codex/backups/miem_workers -maxdepth 1 -type f -name 'miem_workers-*.sql' -delete 2>/dev/null || true
+find "$HOME/backups/miem_workers" -maxdepth 1 -type f -name 'miem_workers-*.sql' -delete 2>/dev/null || true
 printf '%s\n' "Created $backup"