[Star tree] Star tree index validations

[bharath-techie]

Description

• Limit the maximum number of base metrics to 100 with 2.17 experimental release.
• Limit the index.translog.flush_threshold_size to maximum of 512 mb which is the default value of final setting indices.composite_index.translog.max_flush_threshold_size. Since flush is heavy for star tree index, limiting the maximum number of documents during flush will help with the indexing throughput.
• For documents with array values - currently star tree index cannot handle such cases, since 'star' property does not get satisfied.

Related Issues

Resolves #15491

Check List

• Functionality includes testing.
• API changes companion pull request created, if applicable.
• Public documentation issue/PR created, if applicable.

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[github-actions]

❌ Gradle check result for 62a0267: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❌ Gradle check result for 21cf04f: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/OpenSearch/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.x
# Create a new branch
git switch --create backport/backport-15533-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 0512e9ee74a3a8929bbaa3c415cca6ca49791585
# Push it to GitHub
git push --set-upstream origin backport/backport-15533-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-15533-to-2.x.