implemented release build

scripts/prepare-build.mjs

@@ -0,0 +1,36 @@
+/**
+Assembles a self-contained deployment folder at ./build/ from the
+`output: 'standalone'` next build output. Next.js does not include
+.next/static or public/ in .next/standalone by itself, so this script
+copies them in. The result can be deployed as-is and started with
+`node server.js` from inside ./build/, without running `npm install`.
+ */
+
+import { cpSync, existsSync, rmSync } from 'node:fs'
+import path from 'node:path'
+
+const root = path.resolve(import.meta.dirname, '..')
+const standaloneDir = path.join(root, '.next', 'standalone')
+const buildDir = path.join(root, 'build')
+
+if (!existsSync(standaloneDir)) {
+    console.error(
+        `${standaloneDir} not found. Run "next build" with output: 'standalone' set in next.config.ts first.`
+    )
+    process.exit(1)
+}
+
+rmSync(buildDir, { recursive: true, force: true })
+cpSync(standaloneDir, buildDir, { recursive: true })
+cpSync(
+    path.join(root, '.next', 'static'),
+    path.join(buildDir, '.next', 'static'),
+    { recursive: true }
+)
+
+const publicDir = path.join(root, 'public')
+if (existsSync(publicDir)) {
+    cpSync(publicDir, path.join(buildDir, 'public'), { recursive: true })
+}
+
+console.log(`build assembled at ${buildDir}`)