Build the Linux AppImage on a GitHub Actions Linux runner and attach it to each release.

The release is assembled on Windows, and the AppImage needs Linux (the translator's native build and
appimagetool), so releases carried no Linux download. .github/workflows/linux-appimage.yml runs when a
release is published, or by hand for a tag: it builds the translator, takes the button art from the
release's own app zip, runs tools/make_appimage.py, checks that the AppImage starts and uploads it with
its SHA-256 to that release. tools/make_appimage.py takes --prompt-art as make_kit.py does and bundles
pillow, so an AppImage build can draw the Xbox, PlayStation and keyboard prompts.

Pull request #273 by loteran, taken as it is. Added: the workflow installs glslc and spirv-tools, which
make_appimage.py needs since the runtime's shaders are compiled at build time.

The workflow does nothing until this file is on the repository's default branch on GitHub; from then on
every published release starts it, with write access to that release. It was not run here, and
make_appimage.py only passes a syntax check on Windows.

Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>

.github/workflows/linux-appimage.yml

@@ -0,0 +1,68 @@
+# The Linux AppImage of each release (tools/make_appimage.py), built on a Linux runner and attached to the release
+# itself: the release is assembled on Windows (tools/make_release.py), and the AppImage needs Linux (the translator's
+# NativeAOT build for linux-x64, appimagetool). It holds the build kit only, no game files, as the setup does.
+name: Linux AppImage
+
+on:
+  release:
+    types: [published]
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Release tag to build the AppImage for (it replaces one already attached)'
+        required: true
+
+permissions:
+  contents: write   # gh release upload
+
+concurrency:
+  group: linux-appimage-${{ github.event.release.tag_name || inputs.tag }}
+
+jobs:
+  appimage:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 60
+    env:
+      TAG: ${{ github.event.release.tag_name || inputs.tag }}
+      GH_TOKEN: ${{ github.token }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.release.tag_name || inputs.tag }}
+      - uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '10.0.x'
+      - uses: astral-sh/setup-uv@v6
+      - name: Shader compilers
+        # make_appimage.py compiles the runtime's own shaders (tools/build_shaders.py: glslc, spirv-as, spirv-val)
+        run: sudo apt-get update && sudo apt-get install -y glslc spirv-tools
+      - name: Shader translator and VMA
+        run: |
+          uv venv -q --python 3.12 .venv
+          uv pip install -q --python .venv/bin/python pillow
+          .venv/bin/python tools/build_xlate.py
+          .venv/bin/python -c 'import sys; sys.path.insert(0, "tools"); import build_game; print("VMA:", build_game.vma_include())'
+      - name: Button art from the release's app zip
+        run: |
+          # make_release.py uploads the zip with the release; wait for it if the release was published first
+          for i in $(seq 1 20); do
+            gh release download "$TAG" -p 'NX2navi-app-*.zip' -D "$RUNNER_TEMP/app" && break
+            echo "no app zip on $TAG yet ($i)"; sleep 30
+          done
+          unzip -q "$RUNNER_TEMP"/app/NX2navi-app-*.zip 'prompt-art/*' -d "$RUNNER_TEMP/app" || true
+          ls -d "$RUNNER_TEMP/app/prompt-art" 2>/dev/null || echo "::warning::no prompt-art in the app zip: the AppImage's builds keep the Switch prompts"
+      - name: AppImage
+        run: |
+          uv python install -q 3.14
+          py=$(find "$(uv python dir)" -maxdepth 1 -type d -name 'cpython-3.14.*-linux-x86_64-gnu' | sort -V | tail -1)
+          curl -fsSL -o "$RUNNER_TEMP/appimagetool" \
+            https://github.com/AppImage/appimagetool/releases/download/continuous/appimagetool-x86_64.AppImage
+          chmod +x "$RUNNER_TEMP/appimagetool"
+          art=(); [ -d "$RUNNER_TEMP/app/prompt-art" ] && art=(--prompt-art "$RUNNER_TEMP/app/prompt-art")
+          APPIMAGE_EXTRACT_AND_RUN=1 .venv/bin/python tools/make_appimage.py --python "$py" \
+            --appimagetool "$RUNNER_TEMP/appimagetool" --out dist "${art[@]}"
+          appimage=$(ls dist/NX2navi-Linux-*-x86_64.AppImage)
+          APPIMAGE_EXTRACT_AND_RUN=1 "$appimage" --help | head -3
+          (cd dist && sha256sum NX2navi-Linux-*-x86_64.AppImage > SHA256SUMS-linux.txt && cat SHA256SUMS-linux.txt)
+      - name: Attach to the release
+        run: gh release upload "$TAG" --clobber dist/NX2navi-Linux-*-x86_64.AppImage dist/SHA256SUMS-linux.txt