Is your feature request related to a problem?
There is currently no way to run integration tests against a Remote Store enabled cluster in this repository. As Remote Store adoption grows in OpenSearch, we cannot verify that Remote Store related ISM features work correctly through integration tests.
Additionally, warm and search node roles—which are commonly used in Remote Store deployments for tiered storage and reader/writer separation—are unavailable in the current test infrastructure.

What solution would you like?

1. Add a remoteStoreIntegTest Gradle task

   • Test cluster with Remote Store enabled (using fs type repository)
   • Segment Replication enabled
   • Include warm and search node roles

2. Add RemoteStoreSmokeIT as a minimal smoke test

   • Create index on Remote Store cluster
   • Apply a simple policy (e.g., force_merge)
   • Verify execution completes successfully

Once this is completed, we can add integration tests for Remote Store related features like #1531.

What alternatives have you considered?

• Adding Remote Store settings to the existing integTest task with a system property flag (e.g., -DremoteStore=true).
• Testing manually with a local Docker-based Remote Store cluster
• Using mocked responses in unit tests to simulate Remote Store behavior

Do you have any additional context?

• I'm working on [FEATURE] ISM action to auto scale down writers on index migration for Reader/Writer Separation #1531 and I noticed current ci doesn't have remote store setup
• I am interested in contributing this feature