I would like to contribute a new OneOfValidator for the Hibernate Validator project.

This validator checks if a given CharSequence matches one of the allowed values specified in the OneOf annotation.

Features:

• Validates if a CharSequence is one of the allowed values.

• Supports case-sensitive and case-insensitive validation based on the ignoreCase flag in the OneOf annotation.

• Supports both Enum constants and manually provided allowed values.

The validator has been implemented as follows:

• OneOfValidator class implements ConstraintValidator<OneOf, CharSequence>.

• Adds values from allowedValues() and enumClass() in the OneOf annotation for validation.

• Provides methods to handle case-sensitive and case-insensitive validation.