Add e2e tests

.github/workflows/e2e.yml

@@ -0,0 +1,70 @@
+name: E2E Tests
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  e2e-tests:
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        node-version: [18, 20, 22]
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+          cache: "npm"
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Setup package managers (Ubuntu/macOS)
+        if: matrix.os != 'windows-latest'
+        run: |
+          # Install yarn
+          npm install -g yarn
+
+          # Install pnpm
+          npm install -g pnpm
+
+          # Verify installations
+          npm --version
+          yarn --version
+          pnpm --version
+
+      - name: Setup package managers (Windows)
+        if: matrix.os == 'windows-latest'
+        run: |
+          # Install yarn
+          npm install -g yarn
+
+          # Install pnpm
+          npm install -g pnpm
+
+          # Verify installations
+          npm --version
+          yarn --version
+          pnpm --version
+        shell: pwsh
+
+      - name: Install safe-chain globally
+        run: npm install -g .
+
+      - name: Run unit tests
+        run: npm test
+
+      - name: Run linting
+        run: npm run lint
+
+      - name: Run E2E tests
+        run: npm run test:e2e