ci: 将 GitLab CI 迁移至 GitHub Actions

- 新增 .github/workflows/build.yml
- 构建阶段：pnpm 安装、生成 sitemap、构建前端
- Docker 阶段：构建并推送镜像至 ghcr.io
- 删除 .gitlab-ci.yml

Made-with: Cursor

Author: safe1ine

.github/workflows/build.yml

@@ -0,0 +1,87 @@
+name: Build and Push
+
+on:
+  push:
+    branches:
+      - main
+      - dev
+  pull_request:
+    branches:
+      - main
+      - dev
+
+env:
+  NODE_VERSION: "20"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: latest
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+          cache: "pnpm"
+
+      - name: Install dependencies
+        working-directory: frontend
+        run: pnpm install --frozen-lockfile
+
+      - name: Generate sitemap
+        working-directory: frontend
+        run: |
+          sudo apt-get update && sudo apt-get install -y python3 python3-pip
+          pip3 install requests --break-system-packages
+          python3 scripts/generate-sitemap.py || true
+
+      - name: Build
+        working-directory: frontend
+        run: pnpm run build
+
+      - name: Upload dist
+        uses: actions/upload-artifact@v4
+        with:
+          name: dist
+          path: frontend/dist/
+
+  docker:
+    needs: build
+    runs-on: ubuntu-latest
+    if: github.event_name == 'push' && (github.ref == 'refs/heads/main' || github.ref == 'refs/heads/dev')
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download dist
+        uses: actions/download-artifact@v4
+        with:
+          name: dist
+
+      - name: Copy dist to docker
+        run: cp -r dist frontend/docker/dist
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          context: frontend/docker
+          push: true
+          tags: |
+            ghcr.io/${{ github.repository_owner }}/monkeycode-frontend:${{ github.sha }}
+            ghcr.io/${{ github.repository_owner }}/monkeycode-frontend:latest
+          platforms: linux/amd64

.gitlab-ci.yml

@@ -8,4 +8,6 @@ MonkeyCode 是由长亭科技推出的企业级 AI 开发平台。
 
 ## 快速开始
 
-详见 [frontend/README.md](./frontend/README.md)。
+```bash
+cd frontend && pnpm install && pnpm dev
+```