fix: make test suite runnable without DB/Chrome, add tests to CI

- Refactor index.ts to skip start() when NODE_ENV=test
- Add test setup with mocks for db, keys, browser, verification, email, usage
- Add vitest.config.ts with setup file
- Rewrite tests to work with mocks (42 tests, all passing)
- Add new tests: signup 410, recovery validation, CORS headers, error format, API root
- Add test step to CI pipeline before Docker build

.forgejo/workflows/deploy.yml

@@ -13,6 +13,19 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v4
 
+    - name: Setup Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '22'
+
+    - name: Install dependencies
+      run: npm ci
+
+    - name: Run tests
+      run: npm test
+      env:
+        NODE_ENV: test
+
     - name: Set up QEMU
       uses: docker/setup-qemu-action@v3