chore(ci): add GitHub Actions workflow

- Add CI pipeline for format, lint, and typecheck
- Add test execution workflow

Author: NeaByteLab

.github/workflows/ci.yaml

@@ -0,0 +1,36 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  build-check:
+    name: Build Check (${{ matrix.os }})
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Setup Deno
+        uses: denoland/setup-deno@v2
+        with:
+          deno-version: v2.5.4
+
+      - name: Format check
+        run: deno fmt --check src/
+
+      - name: Lint
+        run: deno lint src/
+
+      - name: Type check
+        run: deno check src/index.ts
+
+      - name: Test
+        run: deno test tests/ --allow-read