fix: Treat example values starting with numbers as strings (#4999)

[zero2top]

Pull Request

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Description

This PR fixes an issue where example values that begin with a digit (e.g., "5 lacs per annum") are incorrectly parsed as a numeric literal instead of a string.

The root cause was that Json31.mapper().readTree(...) interprets any string that starts with a digit as JSON numeric content, resulting in the loss of the remaining string.

What this PR changes

Updated AnnotationsUtils#getSchemaFromAnnotation to ensure that example values beginning with digits are always treated as strings.

Added a test case testExampleStartingWithNumberShouldBeString to verify the expected behavior.

Fixes: #4999

Type of Change

• Bug fix

• Tests

Checklist

1. I have added/updated tests as needed
2. The PR title is descriptive
3. The code builds and passes tests locally
4. I have linked the related issue (#4999)

Example before the fix:

"example": 5

After the fix:

"example": "5 lacs per annum"