fix(ci): wait for e2e port to free between suite spawns

scripts/run-e2e-suite.mjs

@@ -1,20 +1,50 @@
 import { readdir } from 'node:fs/promises'
 import { join } from 'node:path'
 import { spawn } from 'node:child_process'
+import { createServer } from 'node:net'
 
 const root = new URL('..', import.meta.url)
 const e2eDir = new URL('../tests/e2e', import.meta.url)
 
 const extraArgs = process.argv.slice(2)
 const pnpmBin = process.platform === 'win32' ? 'pnpm.cmd' : 'pnpm'
 
+// All e2e suites bind Nuxt to this port (see tests/e2e/*.e2e.test.ts).
+// Each suite is run as its own `vitest run` process; we must wait for the
+// previous suite's Nuxt server to release the socket before spawning the
+// next one, otherwise the next boot fails with EADDRINUSE.
+const E2E_PORT = 4327
+const E2E_HOST = '127.0.0.1'
+const PORT_FREE_TIMEOUT_MS = 15_000
+const PORT_FREE_POLL_MS = 200
+
+async function isPortFree(port, host) {
+  return new Promise((resolve) => {
+    const tester = createServer()
+    tester.once('error', () => resolve(false))
+    tester.once('listening', () => {
+      tester.close(() => resolve(true))
+    })
+    tester.listen(port, host)
+  })
+}
+
+async function waitForPortFree(port, host, timeoutMs) {
+  const deadline = Date.now() + timeoutMs
+  while (Date.now() < deadline) {
+    if (await isPortFree(port, host)) return
+    await new Promise(r => setTimeout(r, PORT_FREE_POLL_MS))
+  }
+  throw new Error(`Port ${port} on ${host} still in use after ${timeoutMs}ms`)
+}
+
 const files = (await readdir(e2eDir))
   .filter(name => name.endsWith('.e2e.test.ts'))
   .sort()
 
 for (const file of files) {
   const filePath = join('tests', 'e2e', file)
   console.log(`\n[e2e] ${filePath}`)
 
   const exitCode = await new Promise((resolve, reject) => {
     const child = spawn(
@@ -34,4 +64,6 @@
   if (exitCode !== 0) {
     process.exit(exitCode)
   }
+
+  await waitForPortFree(E2E_PORT, E2E_HOST, PORT_FREE_TIMEOUT_MS)
 }