Add execute tool + scratch pad tests

[nathaliellenaa]

Description

Add execute tool + scratch pad tests

Related Issues

Resolves #[Issue number to be closed when this PR is merged]

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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[mingshl]

thanks for verifying the exception in UT.

[dhrubo-os]

 Could not determine the dependencies of task ':opensearch-ml-plugin:dependencyLicenses'.
> Failed to query the value of task ':opensearch-ml-plugin:dependencyLicenses' property 'dependencies'.
   > Could not resolve all dependencies for configuration ':opensearch-ml-plugin:runtimeClasspath'.
      > Could not resolve software.amazon.awssdk:kms:2.32.29.
        Required by:
            project :opensearch-ml-plugin > project :opensearch-ml-algorithms > software.amazon.awssdk:bom:2.32.29
            project :opensearch-ml-plugin > project :opensearch-ml-algorithms > org.opensearch:opensearch-remote-metadata-sdk-ddb-client:3.4.0.0-SNAPSHOT:20251106.022320-9
         > Conflict found for module 'software.amazon.awssdk:kms': between versions 2.32.29 and 2.26.3
      > Could not resolve software.amazon.awssdk:dynamodb:2.32.29.
        Required by:
            project :opensearch-ml-plugin > project :opensearch-ml-algorithms > software.amazon.awssdk:bom:2.32.29
            project :opensearch-ml-plugin > project :opensearch-ml-algorithms > software.amazon.awssdk:bom:2.32.29 > software.amazon.awssdk:dynamodb-enhanced:2.32.29
         > Conflict found for module 'software.amazon.awssdk:dynamodb': between versions 2.32.29 and 2.26.3
      > Could not resolve org.dafny:DafnyRuntime:4.9.0.
        Required by:
            project :opensearch-ml-plugin > project :opensearch-ml-algorithms > org.opensearch:opensearch-remote-metadata-sdk-ddb-client:3.4.0.0-SNAPSHOT:20251106.022320-9 > software.amazon.cryptography:aws-database-encryption-sdk-dynamodb:3.9.0
            project :opensearch-ml-plugin > project :opensearch-ml-algorithms > org.opensearch:opensearch-remote-metadata-sdk-ddb-client:3.4.0.0-SNAPSHOT:20251106.022320-9 > software.amazon.cryptography:aws-cryptographic-material-providers:1.11.0

Deprecated Gradle features were used in this build, making it incompatible with Gradle 9.0.

Seems like we started having a dependency conflict issue.

[mingshl]

dependency issue should be fixed in this PRhttps://github.com//pull/4405. rerunning CIs

[nathaliellenaa]

Failing tests are unrelated

RestBedRockInferenceIT > test_bedrock_multimodal_model_empty_imageInput FAILED
    java.lang.AssertionError: Failing test case name: without_step_size, inference result: {"error":{"root_cause":[{"type":"status_exception","reason":"Error from remote service: {\"message\":\"The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details.