fix: private attributes not being accessible in dart

[ChiragAgg5k]

What does this PR do?

fixes environment variables like _APP_DOMAIN_SITES being marked as private and hence the model not working at all.

Test Plan

updated dart tests, eg:

import 'package:dart_appwrite/models.dart';
import 'package:test/test.dart';

void main() {
  group('ConsoleVariables', () {

    test('model', () {
      final model = ConsoleVariables(
        APP_DOMAIN_TARGET_CNAME: 'appwrite.io',
        APP_DOMAIN_TARGET_A: '127.0.0.1',
        APP_DOMAIN_TARGET_AAAA: '::1',
        APP_STORAGE_LIMIT: 30000000,
        APP_COMPUTE_SIZE_LIMIT: 30000000,
        APP_USAGE_STATS: 'enabled',
        APP_VCS_ENABLED: true,
        APP_DOMAIN_ENABLED: true,
        APP_ASSISTANT_ENABLED: true,
        APP_DOMAIN_SITES: 'sites.localhost',
        APP_DOMAIN_FUNCTIONS: 'functions.localhost',
        APP_OPTIONS_FORCE_HTTPS: 'enabled',
        APP_DOMAINS_NAMESERVERS: 'ns1.example.com,ns2.example.com',
      );

      final map = model.toMap();
      final result = ConsoleVariables.fromMap(map);

      expect(result.APP_DOMAIN_TARGET_CNAME, 'appwrite.io');
      expect(result.APP_DOMAIN_TARGET_A, '127.0.0.1');
      expect(result.APP_DOMAIN_TARGET_AAAA, '::1');
      expect(result.APP_STORAGE_LIMIT, 30000000);
      expect(result.APP_COMPUTE_SIZE_LIMIT, 30000000);
      expect(result.APP_USAGE_STATS, 'enabled');
      expect(result.APP_VCS_ENABLED, true);
      expect(result.APP_DOMAIN_ENABLED, true);
      expect(result.APP_ASSISTANT_ENABLED, true);
      expect(result.APP_DOMAIN_SITES, 'sites.localhost');
      expect(result.APP_DOMAIN_FUNCTIONS, 'functions.localhost');
      expect(result.APP_OPTIONS_FORCE_HTTPS, 'enabled');
      expect(result.APP_DOMAINS_NAMESERVERS, 'ns1.example.com,ns2.example.com');
    });
  });
}

Related PRs and Issues

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