feat: sync httpdns sdk/platform updates without large binaries

HttpDNSSDK/sdk/flutter/new_httpdns/README.md

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+# HTTPDNS Flutter SDK (SNI Hidden v1.0.0)
+
+## 1. Initialization
+
+```dart
+import 'package:new_httpdns/new_httpdns.dart';
+
+await NewHttpdns.init(
+  appId: 'app1f1ndpo9',
+  primaryServiceHost: 'httpdns-a.example.com',
+  backupServiceHost: 'httpdns-b.example.com', // optional
+  servicePort: 443,
+  secretKey: 'your-sign-secret', // optional if sign is enabled
+);
+
+await NewHttpdns.setHttpsRequestEnabled(true);
+await NewHttpdns.build();
+```
+
+## 2. Resolve
+
+```dart
+final result = await NewHttpdns.resolveHostSyncNonBlocking(
+  'api.business.com',
+  ipType: 'both',
+);
+
+final ipv4 = result['ipv4'] ?? <String>[];
+final ipv6 = result['ipv6'] ?? <String>[];
+```
+
+## 3. Official HTTP Adapter (IP + Host)
+
+```dart
+final adapter = NewHttpdns.createHttpAdapter(
+  options: const NewHttpdnsAdapterOptions(
+    ipType: 'auto',
+    connectTimeoutMs: 3000,
+    readTimeoutMs: 5000,
+    allowInsecureCertificatesForDebugOnly: false,
+  ),
+);
+
+final resp = await adapter.request(
+  Uri.parse('https://api.business.com/v1/ping'),
+  method: 'GET',
+  headers: {'Accept': 'application/json'},
+);
+
+print(resp.statusCode);
+print(resp.usedIp);
+```
+
+Behavior is fixed:
+- Resolve host by `/resolve`.
+- Connect to resolved IP over HTTPS.
+- Keep `Host` header as the real business domain.
+- No fallback to domain direct request.
+
+## 4. Public Errors
+
+- `NO_IP_AVAILABLE`
+- `TLS_EMPTY_SNI_FAILED`
+- `HOST_ROUTE_REJECTED`
+- `RESOLVE_SIGN_INVALID`
+
+## 5. Deprecated Params Removed
+
+The public init API no longer accepts:
+- `accountId`
+- `serviceDomain`
+- `endpoint`
+- `aesSecretKey`