feat(schema): add support for Type::map() to validate key-value objects

add support for Type::map() to validate key-value objects

feat(arrayof): allow optional acceptance of string keys

Added support for string keys in ArrayOf types via acceptStringKeys() method.
By default, keys must be integers. When enabled, string keys are trimmed and accepted.

Add allowEmptyData option to validation processor

• Add allowEmptyData parameter to process() method
• Skip validation when empty data is explicitly allowed
• Maintain backward compatibility with default false value

Support psr/http-message 1.0+2.0

Update dependency constraint to "^1.0 || ^2.0"

Initial commit for php-requestkit library

1.0.0

Initial commit for php-requestkit library