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

.github/workflows/test.yml

@@ -0,0 +1,40 @@
+name: Tests
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  unit:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install bun
+        uses: oven-sh/setup-bun@v2
+      - name: Install dependencies
+        run: bun install --include=dev
+      - name: Check formatting
+        run: bun run check
+      - name: ESLint
+        run: bun run lint
+      - name: Typecheck
+        run: bun run typecheck
+      - name: Run tests
+        run: bun run test
+  integration:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install bun
+        uses: oven-sh/setup-bun@v2
+      - name: Setup Node
+        # The built Nitro server and the WASM Postgres host run under node.
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+      - name: Install dependencies
+        run: bun install --include=dev
+      - name: Run integration tests
+        run: bun run test:integration