test(solid-query): add e2e tests for head() async loader fix

Adds comprehensive playwright tests verifying the head() re-execution fix:
- Verifies page title updates correctly on back navigation after login
- Tests fallback title when loader returns null
- Tests logout flow with correct title updates
- Verifies race condition handling with rapid navigation

Also fixes package.json start script to use 'pnpm dlx' instead of
deprecated 'pnpx' command for compatibility with modern pnpm versions.

All tests passing, confirming non-blocking head() re-execution works
correctly after async loaders complete.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

Author: yanghuidong

e2e/solid-start/basic-solid-query/package.json

@@ -8,7 +8,7 @@
     "dev:e2e": "vite dev",
     "build": "vite build && tsc --noEmit",
     "preview": "vite preview",
-    "start": "pnpx srvx --prod -s ../client dist/server/server.js",
+    "start": "pnpm dlx srvx --prod -s ../client dist/server/server.js",
     "test:e2e": "rm -rf port*.txt; playwright test --project=chromium"
   },
   "dependencies": {

e2e/solid-start/basic-solid-query/tests/head.spec.ts

@@ -0,0 +1,99 @@
+import { expect, test } from '@playwright/test'
+
+test.describe('head() function with async loaders and back navigation', () => {
+  test.beforeEach(async ({ page }) => {
+    // Clear auth state before each test
+    await page.goto('/')
+    await page.evaluate(() => localStorage.clear())
+  })
+
+  test('page title updates correctly when navigating back after login', async ({
+    page,
+  }) => {
+    // Step 1: Visit article while unauthenticated
+    await page.goto('/test-head/article/123')
+
+    // Should show "Article Not Found" content and title
+    await expect(page.getByTestId('article-not-found')).toBeVisible()
+    await expect(page).toHaveTitle('Article Not Found')
+
+    // Step 2: Click login link
+    await page.getByTestId('go-to-login-link').click()
+
+    // Should be on login page
+    await expect(page.getByTestId('login-page')).toBeVisible()
+    await expect(page).toHaveTitle('Login')
+
+    // Step 3: Simulate login
+    await page.getByTestId('login-button').click()
+
+    // Should be redirected to dashboard
+    await expect(page.getByTestId('dashboard')).toBeVisible()
+    await expect(page).toHaveTitle('Dashboard')
+
+    // Step 4: Navigate back with browser back button
+    // This is the critical test - the bug was that the title wouldn't update
+    await page.goBack()
+
+    // Wait for the article content to load (proves loader ran)
+    await expect(page.getByTestId('article-content')).toBeVisible()
+    await expect(page.getByTestId('article-title')).toContainText(
+      'Article 123 Title',
+    )
+
+    // Critical assertion: page title should update to the actual article title
+    // With the bug, this would remain "Article Not Found"
+    // With the fix, head() re-executes after async loaders complete
+    await expect(page).toHaveTitle('Article 123 Title')
+  })
+
+  test('page title shows correct fallback when loader returns null', async ({
+    page,
+  }) => {
+    // Visit article while unauthenticated
+    await page.goto('/test-head/article/456')
+
+    // Should show fallback content and title
+    await expect(page.getByTestId('article-not-found')).toBeVisible()
+    await expect(page).toHaveTitle('Article Not Found')
+  })
+
+  test('logout flow works correctly', async ({ page }) => {
+    // Set up authenticated state
+    await page.goto('/fake-login')
+    await page.getByTestId('login-button').click()
+
+    // Navigate to article
+    await page.goto('/test-head/article/789')
+    await expect(page.getByTestId('article-content')).toBeVisible()
+    await expect(page).toHaveTitle('Article 789 Title')
+
+    // Click logout button
+    await page.getByTestId('logout-button').click()
+
+    // Page should reload and show not found state
+    await expect(page.getByTestId('article-not-found')).toBeVisible()
+    await expect(page).toHaveTitle('Article Not Found')
+  })
+
+  test('rapid navigation does not cause stale head() execution', async ({
+    page,
+  }) => {
+    // Set up authenticated state
+    await page.goto('/fake-login')
+    await page.getByTestId('login-button').click()
+
+    // Navigate to first article
+    await page.goto('/test-head/article/111')
+    await expect(page).toHaveTitle('Article 111 Title')
+
+    // Rapidly navigate to second article
+    await page.goto('/test-head/article/222')
+    await expect(page).toHaveTitle('Article 222 Title')
+
+    // Title should match the current route, not the previous one
+    const title = await page.title()
+    expect(title).toBe('Article 222 Title')
+    expect(title).not.toBe('Article 111 Title')
+  })
+})