Enable script score to work with model based indices

[ryanbogan]

Description

Previously, an exception would be thrown when attempting to use script score with a model-based index. Since the expected dimensions for a model-based index field are set to -1, there would be a mismatch between the actual dimension of the float array and the expected dimension. This PR retrieves the expected dimensions from the model metadata for model-based indices, thus enabling script score to work as intended.

Issues Resolved

#1554

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed as per the DCO using --signoff

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[navneet1v]

@ryanbogan I don't see the IT for this change. Can you please add an IT for this change

[ryanbogan]

I'm going to remove the * import in the integration test shortly

[ryanbogan]

BWC failures are not related to this PR, and were passing earlier

[navneet1v]

Overall code looks good to me. Let ensure all gh actions are successful.

[martin-gaievski]

Looks good to me, thx. Link checker is failing, but that's not related to changes in this PR

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-1649-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 e608d2de4be4c86b0b45c6211baef91a9c46af22
# Push it to GitHub
git push --set-upstream origin backport/backport-1649-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-1649-to-2.x.