Fix LFS

.forgejo/workflows/docker-publish.yml

@@ -10,13 +10,23 @@ jobs:
   build-and-push:
     runs-on: docker
     steps:
+      # The product-demo videos and their poster JPGs live in Git LFS (see
+      # .gitattributes). The checkout below needs `lfs: true` to smudge the real
+      # binaries, but the runner image ships without the git-lfs executable, so
+      # install it first — otherwise checkout fails with "Unable to locate
+      # executable file: git-lfs".
+      - name: Install Git LFS
+        run: |
+          if command -v sudo >/dev/null 2>&1; then SUDO=sudo; else SUDO=; fi
+          $SUDO apt-get update
+          $SUDO apt-get install -y --no-install-recommends git-lfs
+
       - name: Checkout
         uses: actions/checkout@v4
-        # The product-demo videos and their poster JPGs live in Git LFS
-        # (see .gitattributes). Without this, checkout writes ~130-byte LFS
-        # pointer text files, the Docker build copies those stubs into
-        # frontend/dist/video/*, and the server serves text as video/mp4 —
-        # so the videos never load in production. Smudge the real binaries.
+        # Without lfs, checkout writes ~130-byte LFS pointer text files, the
+        # Docker build copies those stubs into frontend/dist/video/*, and the
+        # server serves text as video/mp4 — so the videos never load in
+        # production. Smudge the real binaries instead.
         with:
           lfs: true