cluster0: composed ac backend, /issues/ nginx, postgres semi-prod

Compose lab PHP from ac-workspace overlay; 301 /crashes/ → /issues/;
verify on issues path; optional native Postgres on cast01.

Co-authored-by: Cursor <cursoragent@cursor.com>

sim/cluster0/scripts/deploy-postgres-semi.sh

@@ -0,0 +1,32 @@
+#!/bin/sh
+# Optional semi-prod PostgreSQL on cast01 (native Alpine, no Docker).
+set -eu
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+# shellcheck source=/dev/null
+. "$ROOT/scripts/lib/common.sh"
+load_cluster_env
+
+[ "$(host_short)" = "$CAST01_HOST" ] || { log "postgres semi-prod: cast01 only — skip on $(host_short)"; exit 0; }
+
+PG_VER="${POSTGRES_SEMI_VERSION:-16}"
+DB_NAME="${POSTGRES_SEMI_DB:-androidcast_semi_pg}"
+
+if ! apk info -e "postgresql${PG_VER}" >/dev/null 2>&1; then
+  log "install postgresql${PG_VER}"
+  apk add --no-cache "postgresql${PG_VER}" "postgresql${PG_VER}-contrib" || apk add --no-cache postgresql postgresql-contrib
+fi
+
+if [ ! -d /var/lib/postgresql/data/PG_VERSION ]; then
+  log "initdb"
+  mkdir -p /var/lib/postgresql/data
+  chown postgres:postgres /var/lib/postgresql/data
+  su postgres -c "initdb -D /var/lib/postgresql/data"
+fi
+
+rc-service postgresql restart 2>/dev/null || rc-service postgresql start
+sleep 2
+
+su postgres -c "psql -tc \"SELECT 1 FROM pg_database WHERE datname='${DB_NAME}'\" | grep -q 1" \
+  || su postgres -c "createdb ${DB_NAME}"
+
+log "postgres_semi_ok db=${DB_NAME} host=127.0.0.1"