Add workflow to deploy web version

Author: abustany

.github/workflows/pages.yml

@@ -0,0 +1,52 @@
+name: Deploy web version
+
+on:
+  push:
+    branches: [$default-branch]
+
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
+jobs:
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install Nix
+        uses: cachix/install-nix-action@v27
+
+      - name: Run the Magic Nix Cache
+        uses: DeterminateSystems/magic-nix-cache-action@v7
+
+      - name: Setup flake environment
+        run: nix develop -c sleep 0
+        shell: bash
+
+      - name: Build web version
+        run: nix develop -c make build-web
+        shell: bash
+
+      - name: Setup Pages
+        uses: actions/configure-pages@v5
+
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: './build'
+
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4