(CI) factor out shared setup into standalone action

.github/actions/setup-build-env/action.yml

@@ -0,0 +1,29 @@
+name: 'Setup Build Environment'
+description: 'Set up LLVM, MESA, and Flutter for builds'
+runs:
+  using: 'composite'
+  steps:
+    - uses: actions/checkout@v4
+    - name: Setup LLVM
+      uses: KyleMayes/install-llvm-action@v1
+      with:
+        version: "16"
+    - name: Add LLVM to PATH
+      shell: bash
+      run: |
+        echo "${{ github.workspace }}/llvm/bin" >> $GITHUB_PATH
+        echo "LD_LIBRARY_PATH=${{ github.workspace }}/llvm/lib/x86_64-unknown-linux-gnu/" >> $GITHUB_ENV
+    - name: Verify installation
+      shell: bash
+      run: clang --version
+    - name: Install MESA
+      shell: bash
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y xvfb
+        sudo apt-get install -y libosmesa6-dev
+    - name: Set up Flutter
+      uses: subosito/flutter-action@v2
+      with:
+        channel: master
+        architecture: X64

.github/workflows/dart.yml

@@ -10,40 +10,42 @@ jobs:
   update-goldens:
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
-      - name: Setup LLVM
-        uses: KyleMayes/install-llvm-action@v1
-        with:
-          version: "16"  
-      - name: Add LLVM to PATH
-        run: |
-          echo "${{ github.workspace }}/llvm/bin" >> $GITHUB_PATH
-          echo "LD_LIBRARY_PATH=${{ github.workspace }}/llvm/lib/x86_64-unknown-linux-gnu/" >> $GITHUB_ENV
-      - name: Verify installation
-        run: clang --version
-      - name: Install MESA
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y xvfb
-          sudo apt-get install -y libosmesa6-dev
-          #sudo apt-get -y build-dep mesa
-          #git clone https://gitlab.freedesktop.org/mesa/mesa.git
-          #cd mesa
-          #git checkout mesa-23.2.1
-          #mkdir -p out
-          #meson setup builddir/ -Dprefix="$(pwd)/out" -Dosmesa=true -Dglx=xlib -Dgallium-drivers=swrast -Dvulkan-drivers=swrast
-          #meson install -C builddir/
+      - uses: actions/checkout@v4  # This must come first!
+      - uses: ./.github/actions/setup-build-env
+      #- uses: actions/checkout@v4
+      #- name: Setup LLVM
+      #  uses: KyleMayes/install-llvm-action@v1
+      #  with:
+      #    version: "16"  
+      #- name: Add LLVM to PATH
+      #  run: |
+      #    echo "${{ github.workspace }}/llvm/bin" >> $GITHUB_PATH
+      #    echo "LD_LIBRARY_PATH=${{ github.workspace }}/llvm/lib/x86_64-unknown-linux-gnu/" >> $GITHUB_ENV
+      #- name: Verify installation
+      #  run: clang --version
+      #- name: Install MESA
+      #  run: |
+      #    sudo apt-get update
+      #    sudo apt-get install -y xvfb
+      #    sudo apt-get install -y libosmesa6-dev
+      #    #sudo apt-get -y build-dep mesa
+      #    #git clone https://gitlab.freedesktop.org/mesa/mesa.git
+      #    #cd mesa
+      #    #git checkout mesa-23.2.1
+      #    #mkdir -p out
+      #    #meson setup builddir/ -Dprefix="$(pwd)/out" -Dosmesa=true -Dglx=xlib -Dgallium-drivers=swrast -Dvulkan-drivers=swrast
+      #    #meson install -C builddir/
       #- name: Install Vulkan SDK and dependencies
       #  run: |
       #    wget -qO - https://packages.lunarg.com/lunarg-signing-key-pub.asc | sudo apt-key add -
       #    sudo wget -qO /etc/apt/sources.list.d/lunarg-vulkan-jammy.list https://packages.lunarg.com/vulkan/lunarg-vulkan-jammy.list
       #    sudo apt-get update
       #    sudo apt-get install -y vulkan-sdk
-      - name: Set up Flutter
-        uses: subosito/flutter-action@v2
-        with:
-          channel: master
-          architecture: X64
+      #- name: Set up Flutter
+      #  uses: subosito/flutter-action@v2
+      #  with:
+      #    channel: master
+      #    architecture: X64
       - run: cd thermion_dart && dart pub get && xvfb-run dart --enable-experiment=native-assets test test/asset_tests.dart 
       - name: Zip goldens
         run: zip -r goldens.zip ./thermion_dart/test/output