CI: generate docs

.github/workflows/docs.yml

@@ -0,0 +1,46 @@
+name: Documentation
+
+on:
+  push:
+    branches:
+      - 'master'
+  workflow_dispatch:
+
+jobs:
+  build_unix:
+    name: Build
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+
+    - uses: abbbi/github-actions-tune@v1
+
+    - name: Install packages
+      run: |
+        sudo add-apt-repository universe
+        sudo apt-get install -y -qq cmake doxygen
+
+    - name: Generate build system
+      run: cmake -S . -B build -DENABLE_DOCS:BOOL=ON
+
+    - name: Run Doxygen
+      run: make -C build docs
+
+    - name: Copy docs
+      run: |
+        mv -v docs /tmp
+        git switch docs_html
+        git rm -r --ignore-unmatch docs
+        mv -v /tmp/docs/html docs
+
+    - uses: EndBug/add-and-commit@v9
+      with:
+        add: '. --force'
+        cwd: 'docs'
+        message: 'Update documentation'
+        new_branch: 'docs_html'
+        pull: '--ff-only'
+        push: true