feat: 从 SQLite 切换到 PostgreSQL

- Prisma provider 改为 postgresql
- docker-compose 新增 postgres 服务（带健康检查）
- Dockerfile 移除 sqlite3/template.db，改用 npm install prisma 做运行时 schema 同步
- docker-entrypoint.sh 简化为 prisma db push + node server.js

docker-entrypoint.sh

@@ -1,36 +1,7 @@
 #!/bin/sh
 set -e
 
-TEMPLATE="/app/template.db"
-DB="/app/data/prod.db"
-
-if [ ! -f "$DB" ]; then
-  echo "[db] First run — creating database from template"
-  cp "$TEMPLATE" "$DB"
-  exec node server.js
-fi
-
 echo "[db] Syncing schema..."
+npx prisma db push --skip-generate --accept-data-loss
 
-# 1) Create any new tables
-sqlite3 "$TEMPLATE" ".schema" | \
-  sed 's/CREATE TABLE /CREATE TABLE IF NOT EXISTS /g' | \
-  sed 's/CREATE INDEX /CREATE INDEX IF NOT EXISTS /g' | \
-  sed 's/CREATE UNIQUE INDEX /CREATE UNIQUE INDEX IF NOT EXISTS /g' | \
-  sqlite3 "$DB" 2>/dev/null || true
-
-# 2) Add missing columns to existing tables
-for table in $(sqlite3 "$TEMPLATE" "SELECT name FROM sqlite_master WHERE type='table' AND name NOT LIKE 'sqlite_%' AND name NOT LIKE '_prisma%'"); do
-  prod_cols=$(sqlite3 "$DB" "PRAGMA table_info('$table')" 2>/dev/null | cut -d'|' -f2 || echo "")
-
-  sqlite3 "$TEMPLATE" "PRAGMA table_info('$table')" | while IFS='|' read -r _cid name type notnull dflt _pk; do
-    if ! echo "$prod_cols" | grep -qx "$name"; then
-      alter="ALTER TABLE \"$table\" ADD COLUMN \"$name\" $type"
-      [ -n "$dflt" ] && alter="$alter DEFAULT $dflt"
-      sqlite3 "$DB" "$alter" 2>/dev/null && echo "[db] + $table.$name" || true
-    fi
-  done
-done
-
-echo "[db] Schema sync complete"
 exec node server.js