feat: integrate invitation access, world NPCs, and deployment

scripts/run_migrations.ts

@@ -0,0 +1,40 @@
+import { readFile } from 'fs/promises';
+import { resolve } from 'path';
+import { createConnection } from 'mysql2/promise';
+
+const MIGRATIONS = [
+  'src/business/invitation/migrations/create-invitation-codes.sql',
+];
+
+function requiredEnv(name: string): string {
+  const value = String(process.env[name] || '').trim();
+  if (!value) throw new Error(`Missing required environment variable: ${name}`);
+  return value;
+}
+
+async function main(): Promise<void> {
+  const connection = await createConnection({
+    host: requiredEnv('DB_HOST'),
+    port: Number(process.env.DB_PORT || 3306),
+    user: requiredEnv('DB_USERNAME'),
+    password: requiredEnv('DB_PASSWORD'),
+    database: requiredEnv('DB_NAME'),
+    multipleStatements: true,
+    charset: 'utf8mb4',
+  });
+
+  try {
+    for (const migration of MIGRATIONS) {
+      const sql = await readFile(resolve(process.cwd(), migration), 'utf8');
+      await connection.query(sql);
+      console.log(`Applied migration: ${migration}`);
+    }
+  } finally {
+    await connection.end();
+  }
+}
+
+main().catch((error) => {
+  console.error(error instanceof Error ? error.message : error);
+  process.exitCode = 1;
+});