Fix LoadAdditionalListener and bad nodes (Vue 3 migration)

[ciaens]

Resolves: #7235

EDIT: only tested on stable32

📝 Summary

LoadAdditionalListener loads libresign-init (which registers the file actions) but never provides the certificate_ok initial state. The enabled() check always returned false.

During the Vue 3 migration, all file action callbacks were changed to use object destructuring ({ nodes }) but @nextcloud/files passes flat arguments (nodes, view) / (node, view, dir). So nodes was always undefined.

🧪 How to test

1. Access your files
2. Click on a three-dot menu (on a pdf for example)
3. see that the shortcut is there (at the top)

Also, there is the libresign icon applied for signed documents.

✅ Checklist

• I have read and followed the contribution guide.

🤖 AI (if applicable)

• The content of this PR was partially or fully generated using AI -> used it to bisect the changes in releases (between 12.2.X / 12.3.X)

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