feat(packaging): add self-contained AppImage build (x86_64 + aarch64) (#573)

* feat(packaging): add self-contained AppImage build

Bundles the wheel plus PyGObject/GTK3/AppIndicator/IBus typelibs into a
relocatable x86_64 AppImage via linuxdeploy + linuxdeploy-plugin-gtk, so
users get a zero-install, no-sandbox-negotiation alternative alongside
AUR/PyPI. Wired into nightly and tagged releases, plus a smoke-test job
in the PR pipeline since AppImage/ELF bundling can't be verified on a
macOS dev machine.

* feat(packaging): add aarch64 AppImage builds

Parameterizes build.sh on uname -m instead of hardcoding x86_64 (both
linuxdeploy and appimagetool publish aarch64 continuous builds, and
pywhispercpp ships manylinux_aarch64 wheels, so no from-source compile
needed). Adds an arch matrix to the PR smoke-test job, and a second
job in nightly.yml/release.yml that builds on GitHub's free
ubuntu-24.04-arm hosted runner and attaches the aarch64 AppImage to
the same release the x86_64 job already created.

.github/workflows/nightly.yml

@@ -12,6 +12,9 @@ jobs:
   nightly:
     name: Build and Publish Nightly
     runs-on: ubuntu-latest
+    outputs:
+      version: ${{ steps.version.outputs.version }}
+      release_tag: ${{ steps.create_release.outputs.tag }}
 
     steps:
       - name: Checkout code
@@ -33,7 +36,13 @@ jobs:
             portaudio19-dev \
             python3-dev \
             libgirepository1.0-dev \
-            pkg-config
+            libgirepository-2.0-dev \
+            pkg-config \
+            libcairo2-dev \
+            gobject-introspection \
+            gir1.2-gtk-3.0 \
+            gir1.2-appindicator3-0.1 \
+            gir1.2-ibus-1.0
 
       - name: Install build dependencies
         run: |
@@ -80,6 +89,11 @@ jobs:
           done
           ls -la dist/
 
+      - name: Build AppImage (x86_64)
+        run: |
+          bash packaging/appimage/build.sh dist/*.whl "${{ steps.version.outputs.version }}" dist
+          ls -la dist/*.AppImage
+
       - name: Cleanup old nightly releases
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -166,6 +180,14 @@ jobs:
           curl -fsSL https://raw.githubusercontent.com/jatinkrmalik/vocalinux/main/install.sh | bash
           \`\`\`
 
+          #### AppImage (no install, no root)
+          Download the \`.AppImage\` matching your CPU (\`x86_64\` or \`aarch64\`) below:
+          \`\`\`bash
+          chmod +x Vocalinux-${{ steps.version.outputs.version }}-x86_64.AppImage
+          ./Vocalinux-${{ steps.version.outputs.version }}-x86_64.AppImage
+          \`\`\`
+          Requires \`xdotool\`/\`wtype\`/\`ydotool\` on the host for text injection, same as the PyPI install path.
+
           ---
 
           ### Build Information
@@ -184,6 +206,8 @@ jobs:
 
           - **\`vocalinux-${{ steps.version.outputs.version }}-py3-none-any.whl\`** - Python wheel (recommended)
           - **\`vocalinux-${{ steps.version.outputs.version }}.tar.gz\`** - Source distribution
+          - **\`Vocalinux-${{ steps.version.outputs.version }}-x86_64.AppImage\`** - Self-contained, no install (Intel/AMD)
+          - **\`Vocalinux-${{ steps.version.outputs.version }}-aarch64.AppImage\`** - Self-contained, no install (ARM64, added shortly after this release is published)
 
           ---
 
@@ -202,26 +226,85 @@ jobs:
           echo "notes_file=/tmp/release_notes.md" >> $GITHUB_OUTPUT
 
       - name: Create nightly release
+        id: create_release
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
           # Create release with dated tag: nightly-2025-02-11
           RELEASE_TAG="nightly-$(date +%Y-%m-%d)"
-          
+
           # If a release for today already exists, delete it first
           gh release delete "$RELEASE_TAG" --yes --repo ${{ github.repository }} 2>/dev/null || true
           git push origin :refs/tags/"$RELEASE_TAG" 2>/dev/null || true
           git tag -d "$RELEASE_TAG" 2>/dev/null || true
-          
+
           gh release create "$RELEASE_TAG" \
             --title "Nightly Build - ${{ steps.version.outputs.version }}" \
             --notes-file ${{ steps.release_notes.outputs.notes_file }} \
             --prerelease \
             dist/*
 
+          echo "tag=${RELEASE_TAG}" >> "$GITHUB_OUTPUT"
+
       - name: Upload artifacts (backup)
         uses: actions/upload-artifact@v4
         with:
           name: vocalinux-nightly-${{ steps.version.outputs.version }}
           path: dist/
           retention-days: 7
+
+  nightly-appimage-arm64:
+    name: Build and Attach Nightly AppImage (aarch64)
+    runs-on: ubuntu-24.04-arm
+    needs: nightly
+    if: needs.nightly.result == 'success'
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: main
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+          cache: 'pip'
+
+      - name: Install system dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y \
+            portaudio19-dev \
+            python3-dev \
+            libgirepository1.0-dev \
+            libgirepository-2.0-dev \
+            pkg-config \
+            libcairo2-dev \
+            gobject-introspection \
+            gir1.2-gtk-3.0 \
+            gir1.2-appindicator3-0.1 \
+            gir1.2-ibus-1.0
+
+      - name: Install build dependencies
+        run: |
+          python -m pip install --upgrade pip setuptools wheel build
+
+      - name: Build package
+        run: |
+          python -m build
+          ls -la dist/
+
+      - name: Build AppImage (aarch64)
+        run: |
+          bash packaging/appimage/build.sh dist/*.whl "${{ needs.nightly.outputs.version }}" dist
+          ls -la dist/*.AppImage
+
+      - name: Attach to nightly release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          gh release upload "${{ needs.nightly.outputs.release_tag }}" \
+            dist/*.AppImage \
+            --repo ${{ github.repository }} \
+            --clobber