Add comprehensive test coverage for JsonParser

[alxkm]

Summary

This PR adds comprehensive test coverage for the JsonParser utility class, focusing on error handling, edge cases, and previously untested functionality.

Changes

Error Handling Tests (3 tests)

• shouldThrowExceptionWhenJsonIsMalformed - Validates IllegalStateException is thrown for malformed JSON with fromJson(Class)
• shouldThrowExceptionWhenJsonIsMalformedWithType - Validates error handling for fromJson(Type) overload
• shouldThrowExceptionWhenJsonIsMalformedWithTypeReference - Validates error handling for fromJson(TypeReference) overload

Generic Collections Support (2 tests)

• fromJsonToListWithTypeReference - Tests deserialization of JSON arrays to typed List<Integer>
• fromJsonToMapWithTypeReference - Tests deserialization of JSON objects to typed Map<String, String>

Null Parameter Validation (2 tests)

• shouldThrowExceptionWhenValueIsNullInToTypedObject - Ensures null value parameter throws IllegalArgumentException
• shouldThrowExceptionWhenTypeIsNullInToTypedObject - Ensures null type parameter throws IllegalArgumentException

Primitive Type Handling (3 tests)

• fromObjectToPrimitiveInt - Tests conversion to primitive int type
• fromObjectToPrimitiveLong - Tests conversion to primitive long type
• fromObjectToPrimitiveBoolean - Tests conversion to primitive boolean type

Edge Cases (4 tests)

• shouldThrowExceptionWhenConversionFails - Validates NumberFormatException for invalid number formats
• fromEmptyJsonObject - Tests parsing empty JSON object {}
• fromEmptyJsonArray - Tests parsing empty JSON array []
• toTypedObjectWithNonParsableJsonString - Tests fallback behavior when JSON string parsing fails

Testing

All new tests pass and improve overall test coverage for the JsonParser class. The tests validate:

• Error conditions are properly handled
• Generic type deserialization works correctly
• Null parameters are validated
• Primitive types are properly resolved
• Edge cases behave as expected