Cache LFS.

.github/actions/lfs/action.yml

@@ -0,0 +1,21 @@
+name: LFS pull
+description: Cached LFS pull.
+
+runs:
+  using: "composite"
+  steps:
+    - name: Create LFS file list
+      shell: bash
+      run: git lfs ls-files --long | cut -d ' ' -f1 | sort > .lfs-assets-id
+
+    - name: Restore LFS cache
+      uses: actions/cache@v4
+      with:
+        path: .git/lfs/objects
+        key: lfs-${{ hashFiles('.lfs-assets-id') }}
+        restore-keys: lfs-
+        enableCrossOsArchive: true
+
+    - name: Git LFS Pull
+      shell: bash
+      run: git lfs pull