Establish the Koi Swagger parser release

Prepare the OpenAPI parser and Dart generator as a publishable Koi package with CLI entrypoint, docs, examples, tests, and pub.dev release metadata.

Constraint: Initial GitHub import follows koi_blueprint_flutter identity mr.koi <i@mrkoi.is>.

Rejected: Keep local runtime state in the initial repository | .dart_tool, .omx, and pubspec.lock are ignored for a reusable package source tree.

Confidence: high

Scope-risk: moderate

Directive: Keep generated-output behavior covered by parser and generator tests before changing rendering rules.

Tested: dart analyze; dart test; PUB_HOSTED_URL=https://pub.dev dart pub publish --dry-run

Not-tested: End-to-end downstream build_runner compilation of generated Retrofit/Freezed output.

test/utils_test.dart

@@ -0,0 +1,15 @@
+import 'package:koi_swagger_parser/src/util/utils.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('toSnakeCase', () {
+    test('保持常见缩写合并后的文件名可读性', () {
+      expect(toSnakeCase('IoTDeviceResponse'), 'iot_device_response');
+      expect(
+        toSnakeCase('ApiResponse_IoTDeviceListResponse_'),
+        'api_response_iot_device_list_response',
+      );
+      expect(toSnakeCase('HTTPValidationError'), 'http_validation_error');
+    });
+  });
+}