Fix enum decoding issue and improve error message

[oschwald]

• Fix enum pointer decoding with @MaxMindDbCreator
• Update maxmind-db test data submodule
• Improve error messages for constructor argument mismatches

[Copilot]

Pull request overview

This PR fixes a bug where enums with @MaxMindDbCreator would throw exceptions when data was stored via pointers in the database, and improves error messages for constructor argument mismatches.

Key Changes:

• Fixed enum decoding by checking for creator methods before loading constructor metadata in requiresLookupContext()
• Enhanced error messages to distinguish between null-to-primitive issues and type mismatches
• Added comprehensive test coverage for enum pointer decoding and error message improvements

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
src/test/resources/maxmind-db	Updated test data submodule to include new test cases
src/test/java/com/maxmind/db/ReaderTest.java	Added tests for enum creator with pointer data and null-to-primitive error messages; corrected expected IPv6 address format
src/main/java/com/maxmind/db/Decoder.java	Fixed enum pointer decoding logic, improved error messages, and added primitive/boxed type checking
CHANGELOG.md	Documented bug fix and error message improvements

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[Copilot]

[nitpick] The boxedType method uses a chain of if statements to map primitive types to their boxed equivalents. Consider using a switch expression for better readability and maintainability, similar to the pattern used in ConnectionTypeEnum.fromString().

Suggested change

	if (primitive == boolean.class) {
	return Boolean.class;
	}
	if (primitive == byte.class) {
	return Byte.class;
	}
	if (primitive == short.class) {
	return Short.class;
	}
	if (primitive == int.class) {
	return Integer.class;
	}
	if (primitive == long.class) {
	return Long.class;
	}
	if (primitive == float.class) {
	return Float.class;
	}
	if (primitive == double.class) {
	return Double.class;
	}
	if (primitive == char.class) {
	return Character.class;
	}
	return primitive;
	return switch (primitive.getName()) {
	case "boolean" -> Boolean.class;
	case "byte" -> Byte.class;
	case "short" -> Short.class;
	case "int" -> Integer.class;
	case "long" -> Long.class;
	case "float" -> Float.class;
	case "double" -> Double.class;
	case "char" -> Character.class;
	default -> primitive;
	};

[oschwald]

I don't love hardcoding the string values like this. I am going to reject this approach. Another option would be a static map, but the original seems fine, if a bit verbose.