experimental release on github

.github/workflows/build-flatpak.yml

@@ -0,0 +1,36 @@
+name: Build Flatpak
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [ main, master ]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v4
+
+      - name: Install Flatpak tooling
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y flatpak flatpak-builder imagemagick curl
+
+      - name: Configure Flathub and required runtimes
+        run: |
+          flatpak --user remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
+          flatpak --user install -y flathub org.freedesktop.Platform//23.08 org.freedesktop.Sdk//23.08
+
+      - name: Build Flatpak and create bundle
+        run: |
+          chmod +x ./build-flatpak.sh
+          ./build-flatpak.sh
+
+      - name: Upload .flatpak bundle artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: publii-flatpak
+          path: publii.flatpak
+          if-no-files-found: error