let's try this

.forgejo/install-emacs/action.yml

@@ -0,0 +1,13 @@
+name: 'Set up Emacs'
+description: 'Install a specific Emacs version for use in your workflow.'
+author: 'Steve Purcell'
+inputs:
+  version:
+    description: 'The version of Emacs to install, e.g. "24.3", or "snapshot" for a recent development version.'
+runs:
+  using: 'composite'
+  steps:
+    - run: ${{ github.action_path }}/install.sh
+      shell: bash
+      env:
+        INPUT_VERSION: ${{ inputs.version }}