feat: migrate runtime backend to node server

server-node/src/db.ts

@@ -0,0 +1,57 @@
+import fs from 'node:fs';
+import path from 'node:path';
+
+import Database from 'better-sqlite3';
+
+import type { AppConfig } from './config.js';
+
+const schemaSql = `
+CREATE TABLE IF NOT EXISTS users (
+  id TEXT PRIMARY KEY,
+  username TEXT NOT NULL UNIQUE,
+  password_hash TEXT NOT NULL,
+  token_version INTEGER NOT NULL DEFAULT 1,
+  created_at TEXT NOT NULL,
+  updated_at TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS save_snapshots (
+  user_id TEXT PRIMARY KEY,
+  version INTEGER NOT NULL,
+  saved_at TEXT NOT NULL,
+  bottom_tab TEXT NOT NULL,
+  game_state_json TEXT NOT NULL,
+  current_story_json TEXT NOT NULL,
+  updated_at TEXT NOT NULL,
+  FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);
+
+CREATE TABLE IF NOT EXISTS runtime_settings (
+  user_id TEXT PRIMARY KEY,
+  music_volume REAL NOT NULL,
+  updated_at TEXT NOT NULL,
+  FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);
+
+CREATE TABLE IF NOT EXISTS custom_world_profiles (
+  user_id TEXT NOT NULL,
+  profile_id TEXT NOT NULL,
+  payload_json TEXT NOT NULL,
+  updated_at TEXT NOT NULL,
+  PRIMARY KEY (user_id, profile_id),
+  FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);
+`;
+
+export type AppDatabase = Database.Database;
+
+export function createDatabase(config: AppConfig) {
+  const sqliteDir = path.dirname(config.sqlitePath);
+  fs.mkdirSync(sqliteDir, { recursive: true });
+
+  const db = new Database(config.sqlitePath);
+  db.pragma('journal_mode = WAL');
+  db.pragma('foreign_keys = ON');
+  db.exec(schemaSql);
+  return db;
+}