feat: discover local ssh server (#921)

lib/data/model/server/discovery_result.dart

@@ -0,0 +1,49 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+part 'discovery_result.freezed.dart';
+part 'discovery_result.g.dart';
+
+@freezed
+abstract class SshDiscoveryResult with _$SshDiscoveryResult {
+  const factory SshDiscoveryResult({
+    required String ip,
+    required int port,
+    String? banner,
+    @Default(false) bool isSelected,
+  }) = _SshDiscoveryResult;
+
+  factory SshDiscoveryResult.fromJson(Map<String, dynamic> json) => _$SshDiscoveryResultFromJson(json);
+}
+
+@freezed
+abstract class SshDiscoveryReport with _$SshDiscoveryReport {
+  const factory SshDiscoveryReport({
+    required String generatedAt,
+    required int durationMs,
+    required int count,
+    required List<SshDiscoveryResult> items,
+  }) = _SshDiscoveryReport;
+
+  factory SshDiscoveryReport.fromJson(Map<String, dynamic> json) => _$SshDiscoveryReportFromJson(json);
+}
+
+@freezed
+abstract class SshDiscoveryConfig with _$SshDiscoveryConfig {
+  const factory SshDiscoveryConfig({
+    @Default(700) int timeoutMs,
+    @Default(128) int maxConcurrency,
+    @Default(false) bool enableMdns,
+    @Default(4096) int hostEnumerationLimit,
+  }) = _SshDiscoveryConfig;
+}
+
+extension SshDiscoveryConfigX on SshDiscoveryConfig {
+  List<String> toArgs() {
+    final args = <String>[];
+    args.add('--timeout-ms=$timeoutMs');
+    args.add('--max-concurrency=$maxConcurrency');
+    args.add('--host-enumeration-limit=$hostEnumerationLimit');
+    if (enableMdns) args.add('--enable-mdns');
+    return args;
+  }
+}