add gha build workflow for docs

Author: kovaca

.github/workflows/docs.yml

@@ -0,0 +1,50 @@
+name: Deploy Documentation to GitHub Pages
+
+on:
+  push:
+    branches: [main]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+jobs:
+  check-deploy:
+    runs-on: ubuntu-latest
+    outputs:
+      should_deploy: ${{ steps.check.outputs.should_deploy }}
+    steps:
+      - name: Check commit message for [gh-pages]
+        id: check
+        run: |
+          if [[ "${{ github.event.head_commit.message }}" == *"[gh-pages]"* ]] || [[ "${{ github.event_name }}" == "workflow_dispatch" ]]; then
+            echo "should_deploy=true" >> $GITHUB_OUTPUT
+          else
+            echo "should_deploy=false" >> $GITHUB_OUTPUT
+          fi
+
+  build:
+    needs: check-deploy
+    if: needs.check-deploy.outputs.should_deploy == 'true'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build with Astro
+        uses: withastro/action@v2
+        with:
+          path: docs
+
+  deploy:
+    needs: build
+    runs-on: ubuntu-latest
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4