feat: generate slug from text

[Emmynem]

PR Description:

Added Functions

• toSlug(text) → Converts string to lowercase slug (e.g., "Hello World!" → "hello-world")

Why

String manipulation is common in ServiceNow (field values, display names, search filters).
These helpers reduce repetitive regex/code snippets.

Example Usage

gs.info(toSlug("Hello World!"));       // "hello-world"

Pull Request Checklist

Overview

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[am-shakeel]

We already have regexutils available with the same underlying logic. The only difference in this case is the regex expression being used, which can be provided as an input to the existing utility method.

Therefore, this appears to be just an example rather than a new enhancement.