Add CI workflow for test coverage

.github/workflows/test.yml

@@ -0,0 +1,28 @@
+name: Test
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: 'yarn'
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+      - name: Generate SvelteKit types
+        run: yarn prepare
+      - name: Run tests with coverage
+        run: yarn test:coverage
+      - name: Upload coverage report
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-report
+          path: coverage
+          if-no-files-found: warn