Add unit, integration and e2e test suites

tests/{unit,integration,e2e}/, at the repo root (not under frontend/,
since e2e exercises the frontend and PocketBase together) — all
against real code rather than mocks:

- unit/: Vitest (nuxt environment) — pure functions in server/utils
  and shared/utils, plus components/composables via
  @nuxt/test-utils/runtime's mountSuspended.
- integration/: Vitest (node environment) — @nuxt/test-utils/e2e's
  setup() builds and runs the real Nitro server against a real
  ephemeral PocketBase instance, exercising the actual /content/* and
  /admin routes end to end.
- e2e/: Playwright, a real browser against the built app and another
  ephemeral PocketBase, covering the user-facing flows (home, blog
  archive, article detail incl. JSON-LD, category filter, 404s, the
  /admin redirect).

The Vitest/Playwright tooling (and node_modules) stays in frontend/,
the repo's only npm project; its configs just point at ../tests/.
Playwright resolves packages from the node_modules nearest each spec
file, so `npm run test:e2e` first symlinks tests/node_modules to
frontend/node_modules (pretest:e2e, idempotent, gitignored).

tests/support/pocketbase.ts is the shared piece behind integration
and e2e: it downloads the same pinned PocketBase binary
pocketbase/Dockerfile uses, starts it against the real
pocketbase/pb_migrations/ (not a copy), and seeds it from
tests/support/fixtures.ts — so these tests run against the exact
schema and API rules that ship to production, catching the class of
bug that only shows up when PocketBase actually enforces them (e.g. a
wrong filter/fields query string silently returning nothing, or too
much).

CLAUDE.md and docs/frontend.md document the new npm scripts and the
single-test commands for each layer.

tests/e2e/admin-redirect.spec.ts

@@ -0,0 +1,11 @@
+import { expect, test } from '@playwright/test'
+
+test('/admin redirects to the real PocketBase dashboard', async ({ page }) => {
+  await page.goto('/admin')
+
+  await expect(page).toHaveURL(/\/_\/(#.*)?$/)
+  // The static <title> is "PocketBase"; the dashboard SPA then renders its
+  // login view and retitles the page — asserting the live title also proves
+  // the dashboard's own JS bundle loaded and ran correctly through the proxy.
+  await expect(page).toHaveTitle('Superuser login')
+})

tests/e2e/article-detail.spec.ts

@@ -0,0 +1,24 @@
+import { expect, test } from '@playwright/test'
+
+test('article detail renders body, breadcrumb and structured data', async ({ page }) => {
+  await page.goto('/blog/articolo-pubblicato')
+
+  await expect(page.getByRole('heading', { level: 1, name: 'Articolo pubblicato' })).toBeVisible()
+  await expect(page.getByRole('link', { name: 'Economia' })).toHaveAttribute(
+    'href',
+    '/category/economia'
+  )
+  await expect(page.locator('.prose strong')).toHaveText('markdown')
+
+  const jsonLd = await page.locator('script[type="application/ld+json"]').textContent()
+  const data = JSON.parse(jsonLd ?? '{}')
+  expect(data['@type']).toBe('BlogPosting')
+  expect(data.headline).toBe('Articolo pubblicato')
+})
+
+test('unknown article slug renders the 404 page', async ({ page }) => {
+  const response = await page.goto('/blog/non-esiste')
+
+  expect(response?.status()).toBe(404)
+  await expect(page.getByRole('heading', { name: 'Pagina non trovata' })).toBeVisible()
+})

tests/e2e/blog.spec.ts

@@ -0,0 +1,9 @@
+import { expect, test } from '@playwright/test'
+
+test('blog archive lists only published articles', async ({ page }) => {
+  await page.goto('/blog')
+
+  await expect(page.getByRole('link', { name: 'Secondo articolo pubblicato' })).toBeVisible()
+  await expect(page.getByRole('link', { name: 'Articolo pubblicato', exact: true })).toBeVisible()
+  await expect(page.getByText('Articolo in bozza')).toHaveCount(0)
+})

tests/e2e/category.spec.ts

@@ -0,0 +1,14 @@
+import { expect, test } from '@playwright/test'
+
+test('category page filters articles to that category only', async ({ page }) => {
+  await page.goto('/category/attualita')
+
+  await expect(page.getByRole('link', { name: 'Secondo articolo pubblicato' })).toBeVisible()
+  await expect(page.getByRole('link', { name: 'Articolo pubblicato', exact: true })).toHaveCount(0)
+})
+
+test('unknown category slug 404s', async ({ page }) => {
+  const response = await page.goto('/category/non-esiste')
+
+  expect(response?.status()).toBe(404)
+})

tests/e2e/global-setup.ts

@@ -0,0 +1,18 @@
+import { startTestPocketbase } from '../support/pocketbase'
+import { E2E_POCKETBASE_PORT } from '../../frontend/playwright.config'
+
+/**
+ * Starts one PocketBase instance, shared by the whole e2e run, on the fixed
+ * port `playwright.config.ts` also bakes into the Nuxt server's env — so both
+ * sides can reference it without needing an async hand-off between them.
+ *
+ * Playwright keeps this module's closure alive and calls the returned
+ * function as teardown once all tests finish (no separate globalTeardown
+ * file needed).
+ */
+export default async function globalSetup() {
+  const pb = await startTestPocketbase({ port: E2E_POCKETBASE_PORT })
+  return async () => {
+    await pb.stop()
+  }
+}

tests/e2e/home.spec.ts

@@ -0,0 +1,11 @@
+import { expect, test } from '@playwright/test'
+
+test('home page shows the latest published article as featured', async ({ page }) => {
+  await page.goto('/')
+
+  await expect(page.getByRole('heading', { name: 'Secondo articolo pubblicato' })).toBeVisible()
+  await expect(page.getByRole('link', { name: "Leggi l'ultimo articolo" })).toHaveAttribute(
+    'href',
+    '/blog/secondo-articolo'
+  )
+})