test: добавить площадку интеграционного тестирования

- добавлены consumer fixtures для React и Next.js
- добавлены typecheck, production build и браузерные smoke-тесты
- добавлена интеграционная проверка в CI

integration/scripts/serve-static.mjs

@@ -0,0 +1,45 @@
+import fs from 'node:fs'
+import http from 'node:http'
+import path from 'node:path'
+
+const [directory, portValue] = process.argv.slice(2)
+
+if (!directory || !portValue) {
+  throw new Error('Usage: node scripts/serve-static.mjs <directory> <port>')
+}
+
+const root = path.resolve(directory)
+const mimeTypes = {
+  '.css': 'text/css; charset=utf-8',
+  '.html': 'text/html; charset=utf-8',
+  '.js': 'text/javascript; charset=utf-8',
+  '.json': 'application/json; charset=utf-8',
+  '.svg': 'image/svg+xml',
+}
+
+const server = http.createServer((request, response) => {
+  const pathname = decodeURIComponent(new URL(request.url ?? '/', 'http://localhost').pathname)
+  const requestedPath = pathname.endsWith('/') ? `${pathname}index.html` : pathname
+  const filePath = path.resolve(root, `.${requestedPath}`)
+
+  if (filePath !== root && !filePath.startsWith(`${root}${path.sep}`)) {
+    response.writeHead(403).end('Forbidden')
+    return
+  }
+
+  const resolvedPath = fs.existsSync(filePath) && fs.statSync(filePath).isFile()
+    ? filePath
+    : path.join(root, 'index.html')
+
+  if (!fs.existsSync(resolvedPath)) {
+    response.writeHead(404).end('Not found')
+    return
+  }
+
+  response.setHeader('Content-Type', mimeTypes[path.extname(resolvedPath)] ?? 'application/octet-stream')
+  fs.createReadStream(resolvedPath).pipe(response)
+})
+
+server.listen(Number(portValue), '127.0.0.1', () => {
+  console.log(`Serving ${root} on http://127.0.0.1:${portValue}`)
+})