Show ES request previews in Snapshot Restore #42798
Description
When editing/creating snapshots, repositories, and policies, users should have access to a preview that shows the underlying request endpoint and payload. We should also offer a "Copy to clipboard" button, so the user could copy and paste this into Console, and add some text that explains what the user is looking at:
This is the underlying request to Elasticsearch that will {create/update} this {snapshot/repository/policy}.