Read-only mode for Index management

[marius-dr]

Describe the feature:
Allow customized security rules that will provide read-only mode access to the index management feature, leveraging this PR: #67791
Describe a specific use case for the feature:
It's been requested to allow users to search and view indices in the cluster, but without the permissions to do potentially destructive actions on them: like delete, freeze or flush.

The current workaround is really convoluted and involves setting specific cluster privileges and it offers a bad user experience. They can still call the actions like delete, but they'll get a bunch of errors.
Related discuss post:
https://discuss.elastic.co/t/how-to-give-read-only-privileges-in-the-index-management-module/247155

[elasticmachine]

Pinging @elastic/es-ui (Team:Elasticsearch UI)

[sebelga]

This would be part of the workstream "App privileges" in mentioned in #77376 (comment)

[elasticmachine]

Pinging @elastic/kibana-management (Team:Kibana Management)