Update SearchCutoffMs

[amit-ksh]

Pull Request

Related issue

Fixes #1639

What does this PR do?

• Add type and methods for the searchCutoffMs API
• Add tests for the searchCutoffMs API in settings.test.ts and searchCutoffMs.test.ts
• Update the test snapshots
• Update the README

PR checklist

Please check if your PR fulfills the following requirements:

• Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
• Have you read the contributing guidelines?
• Have you made sure that the title is accurate and descriptive of the changes?

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