Introduce CI/CD for testing

.github/actions/setup/action.yml

@@ -0,0 +1,20 @@
+name: "Setup dependencies"
+description: "Prepare repository and all dependencies"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Set up pnpm
+      uses: pnpm/action-setup@v2
+      with:
+          version: 8
+
+    - name: Setup Node.js 20.x
+      uses: actions/setup-node@v3
+      with:
+          node-version: 20.x
+          cache: 'pnpm'
+
+    - name: Install dependencies
+      shell: bash
+      run: pnpm install

.github/workflows/verify.yml

@@ -0,0 +1,49 @@
+name: Verify
+on: [push, pull_request]
+
+jobs:
+    lint:
+        name: Lint
+        runs-on: ubuntu-latest
+        timeout-minutes: 5
+
+        steps:
+            - uses: actions/checkout@v3
+
+            - name: Install dependencies
+              uses: ./.github/actions/setup
+
+            - name: Lint code
+              run: pnpm lint
+
+    build:
+        name: Build
+        needs: lint
+        runs-on: ubuntu-latest
+        timeout-minutes: 5
+
+        steps:
+            - uses: actions/checkout@v3
+
+            - name: Install dependencies
+              uses: ./.github/actions/setup
+
+            - name: Build
+              run: pnpm build
+
+    test:
+        name: Test
+        runs-on: ubuntu-latest
+
+        steps:
+            - uses: actions/checkout@v3
+
+            - name: Install dependencies
+              uses: ./.github/actions/setup
+
+            - name: Run tests
+              uses: nick-fields/retry@v2
+              with:
+                  timeout_minutes: 20
+                  max_attempts: 3
+                  command: pnpm test