Add installer signing with SignPath

Author: AlbrechtL

.github/workflows/windows.yml

@@ -80,13 +80,24 @@ jobs:
             & ISCC /Opublish\ /F$Filename /DGitHash=$git_hash windows_installer.iss
 
       - name: Archive artifacts (welle.io Windows installer)
+        id: upload_artifact
         if: always() && steps.create_installer.outcome == 'success'
         uses: actions/upload-artifact@v4
         with:
           name: welle.io Windows installer
           path: publish\*.exe
           if-no-files-found: error
 
+      - name: Sign installer with SignPath
+        uses: signpath/github-action-submit-signing-request@v1
+        with:
+          api-token: '${{ secrets.SIGNPATH_API_TOKEN }}'
+          organization-id: 'b7a507e8-ab76-445f-bfb5-05944bcbbee9'
+          project-slug: 'welle.io'
+          signing-policy-slug: 'test-signing'
+          github-artifact-id: '${{steps.upload_artifact.outputs.artifact-id}}'
+          wait-for-completion: false
+
       - name: Upload to nightly server
         if: always() && steps.create_installer.outcome == 'success'
         uses: dennisameling/ftp-upload-action@v1