feat: add GitHub Actions workflows for build and deploy preview

- Introduced a new workflow for building the preview site and uploading build artifacts.
- Added a deployment workflow to Cloudflare Pages triggered by the successful completion of the build workflow.
- Configured Node.js and pnpm for dependency management and build processes.

.github/workflows/build-preview.yml

@@ -0,0 +1,37 @@
+name: Build Preview Deployment
+
+on:
+  pull_request:
+    types: [opened, synchronize]
+
+jobs:
+  build-preview:
+    runs-on: ubuntu-latest
+    name: Build Preview Site and Upload Build Artifact
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v2
+        with:
+          version: 8
+
+      - name: Install dependencies
+        working-directory: app
+        run: pnpm install
+
+      - name: Build
+        working-directory: app
+        run: pnpm build
+
+      - name: Upload build artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: preview-build
+          path: app/dist 

.github/workflows/deploy-preview.yml

@@ -0,0 +1,38 @@
+name: Upload Preview Deployment
+
+on:
+  workflow_run:
+    workflows: ['Build Preview Deployment']
+    types:
+      - completed
+
+permissions:
+  actions: read
+  deployments: write
+  contents: read
+  pull-requests: write
+
+jobs:
+  deploy-preview:
+    runs-on: ubuntu-latest
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    name: Deploy Preview to Cloudflare Pages
+    steps:
+      - name: Download build artifact
+        uses: actions/download-artifact@v4
+        id: preview-build-artifact
+        with:
+          name: preview-build
+          path: build
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          run-id: ${{ github.event.workflow_run.id }}
+
+      - name: Deploy to Cloudflare Pages
+        uses: AdrianGonz97/refined-cf-pages-action@v1
+        with:
+          apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
+          accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
+          githubToken: ${{ secrets.GITHUB_TOKEN }}
+          projectName: ${{ secrets.CLOUDFLARE_PROJECT_NAME }}
+          deploymentName: Preview
+          directory: ${{ steps.preview-build-artifact.outputs.download-path }}