add deploy workflow

.github/workflows/deploy.yml

@@ -0,0 +1,36 @@
+name: Deploy GitHub Pages
+
+on:
+  push:
+    branches:
+      - main
+
+defaults:
+  run:
+    working-directory: src
+
+jobs:
+  build-and-deploy:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: '18'
+
+      - name: Install Dependencies
+        run: bun install
+
+      - name: Build
+        run: bun run build:docs
+
+      - name: GitHub Pagesへデプロイ
+        uses: peaceiris/actions-gh-pages@v4
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./docs/.vitepress/dist
+