test(integration): add real-stack integration test suite with PGlite

- PGlite (in-memory WASM Postgres) hosted in a child process, exposed
  via TCP socket; real migrations applied with prisma migrate deploy
- Vitest harness (vitest.integration.config.ts, global-setup spawns
  PGlite + built Nuxt server, per-test TRUNCATE, factories, cookie-jar
  API client); no mocks, zero production code changes
- 50 tests across auth, hunt, team, submit, review, showcase, diashow
  incl. SuperJSON envelope check; *.itest.ts keeps bun test untouched
- CI: parallel unit + integration jobs in .github/workflows/test.yml
- tests/ covered by nuxt typecheck via tests/tsconfig.json reference

vitest.integration.config.ts

@@ -0,0 +1,23 @@
+import { fileURLToPath } from 'node:url';
+import { defineConfig } from 'vitest/config';
+
+const root = (path: string) => fileURLToPath(new URL(path, import.meta.url));
+
+export default defineConfig({
+  resolve: {
+    alias: {
+      '~~': root('.'),
+      '#shared': root('./shared')
+    }
+  },
+  test: {
+    include: ['tests/integration/**/*.itest.ts'],
+    globalSetup: ['tests/integration/global-setup.ts'],
+    setupFiles: ['tests/integration/setup.ts'],
+    fileParallelism: false,
+    // First touch of WASM Postgres can be slow; the build happens in
+    // globalSetup and is not affected by these timeouts.
+    testTimeout: 30_000,
+    hookTimeout: 120_000
+  }
+});