feat(client): 节点 status=down 在列表置灰+「不可用」+禁选(#7 客户端侧)

#7 服务端已在 agent 离线时把节点判 down,但客户端 Node 模型没读 status、
列表照常显示。补:Node.status 字段 + 解析 /v1/nodes 的 status;ServerTile/
_NodeGridTile 在 isDown 时 Opacity 置灰 + 末尾「不可用」+ onTap 禁用。全平台
共享(lib/widgets+screens)。up 节点 Opacity 1.0 无变化,golden 不动。加 down
状态 widget 测试。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/lib/models/node.dart

@@ -16,6 +16,7 @@ class Node {
     this.tag = NodeTag.none,
     this.host = '',
     this.port = 0,
+    this.status = 'up',
   });
 
   /// 服务端 UUID，用于 POST /v1/nodes/{uuid}/connect。
@@ -37,6 +38,12 @@ class Node {
   final String host;
   final int port;
 
+  /// 节点状态(来自 /v1/nodes):'up' 可用;其余(如 'down')= agent 离线/不可用。
+  final String status;
+
+  /// 不可用:status 非 'up'(节点 agent 离线,连了也会 503)。
+  bool get isDown => status != 'up';
+
   /// 延迟标签:测得显示「Nms」,未测显示「—」。
   String get pingLabel => ping > 0 ? '${ping}ms' : '—';
 
@@ -50,6 +57,7 @@ class Node {
         tag: tag,
         host: host,
         port: port,
+        status: status,
       );
 
   String localizedName(AppLang lang) => lang == AppLang.zh ? nameZh : nameEn;

client/lib/screens/nodes_page.dart

@@ -158,38 +158,48 @@ class _NodeGridTile extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final c = context.pangolin;
-    return Material(
-      color: active ? c.accentSubtle : c.surface,
-      shape: RoundedRectangleBorder(
-        borderRadius: BorderRadius.circular(PangolinRadius.lg),
-        side: BorderSide(color: active ? c.accentBorder : c.border, width: 1.5),
-      ),
-      clipBehavior: Clip.antiAlias,
-      child: InkWell(
-        onTap: onTap,
-        child: Padding(
-          padding: const EdgeInsets.symmetric(horizontal: 15, vertical: 11),
-          child: Row(children: [
-            CountryCode(code: node.code, active: active),
-            const SizedBox(width: 12),
-            Expanded(
-              child: Column(crossAxisAlignment: CrossAxisAlignment.start, mainAxisSize: MainAxisSize.min, children: [
-                Text(node.localizedName(lang),
-                    overflow: TextOverflow.ellipsis,
-                    style: PangolinText.sm.copyWith(color: c.fg1, fontWeight: FontWeight.w600, fontSize: 14.5)),
-                Text(node.localizedSub(lang),
-                    overflow: TextOverflow.ellipsis,
-                    style: PangolinText.caption.copyWith(color: c.fg3, fontWeight: FontWeight.w400)),
-              ]),
-            ),
-            const SizedBox(width: 8),
-            Column(mainAxisSize: MainAxisSize.min, crossAxisAlignment: CrossAxisAlignment.end, children: [
-              Text(node.pingLabel, style: PangolinText.mono.copyWith(color: c.fg2, fontSize: 12)),
-              const SizedBox(height: 5),
-              SignalBars(ping: node.ping),
+    final down = node.isDown; // 节点不可用(agent 离线):置灰 + 「不可用」+ 禁选。
+    final unavail = lang == AppLang.zh ? '不可用' : 'Unavailable';
+    return Opacity(
+      opacity: down ? 0.55 : 1.0,
+      child: Material(
+        color: (active && !down) ? c.accentSubtle : c.surface,
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(PangolinRadius.lg),
+          side: BorderSide(color: (active && !down) ? c.accentBorder : c.border, width: 1.5),
+        ),
+        clipBehavior: Clip.antiAlias,
+        child: InkWell(
+          onTap: down ? null : onTap,
+          child: Padding(
+            padding: const EdgeInsets.symmetric(horizontal: 15, vertical: 11),
+            child: Row(children: [
+              CountryCode(code: node.code, active: active && !down),
+              const SizedBox(width: 12),
+              Expanded(
+                child: Column(crossAxisAlignment: CrossAxisAlignment.start, mainAxisSize: MainAxisSize.min, children: [
+                  Text(node.localizedName(lang),
+                      overflow: TextOverflow.ellipsis,
+                      style: PangolinText.sm.copyWith(color: c.fg1, fontWeight: FontWeight.w600, fontSize: 14.5)),
+                  Text(node.localizedSub(lang),
+                      overflow: TextOverflow.ellipsis,
+                      style: PangolinText.caption.copyWith(color: c.fg3, fontWeight: FontWeight.w400)),
+                ]),
+              ),
+              const SizedBox(width: 8),
+              if (down)
+                Text(unavail,
+                    style: PangolinText.caption.copyWith(color: c.danger, fontWeight: FontWeight.w600, fontSize: 12))
+              else ...[
+                Column(mainAxisSize: MainAxisSize.min, crossAxisAlignment: CrossAxisAlignment.end, children: [
+                  Text(node.pingLabel, style: PangolinText.mono.copyWith(color: c.fg2, fontSize: 12)),
+                  const SizedBox(height: 5),
+                  SignalBars(ping: node.ping),
+                ]),
+                if (active) ...[const SizedBox(width: 8), Icon(PangolinIcons.check, size: 18, color: c.accent)],
+              ],
             ]),
-            if (active) ...[const SizedBox(width: 8), Icon(PangolinIcons.check, size: 18, color: c.accent)],
-          ]),
+          ),
         ),
       ),
     );

client/lib/state/nodes_provider.dart

@@ -73,6 +73,7 @@ class NodesNotifier extends AsyncNotifier<List<Node>> {
         tier: m['tier'] as String? ?? 'free',
         host: m['host'] as String? ?? '',
         port: (m['port'] as num?)?.toInt() ?? 0,
+        status: m['status'] as String? ?? 'up',
         ping: 0, // 由 _measure 实测回填
       );
     }).toList();

client/lib/widgets/server_tile.dart

@@ -43,33 +43,43 @@ class ServerTile extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final c = context.pangolin;
+    final down = node.isDown; // 节点不可用(agent 离线):置灰 + 「不可用」+ 禁选。
+    final unavail = lang == AppLang.zh ? '不可用' : 'Unavailable';
     return InkWell(
-      onTap: onTap,
-      child: Container(
-        color: active ? c.accentSubtle : Colors.transparent,
-        padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 12),
-        child: Row(
-          children: [
-            CountryCode(code: node.code, active: active),
-            const SizedBox(width: 13),
-            Expanded(
-              child: Column(
-                crossAxisAlignment: CrossAxisAlignment.start,
-                children: [
-                  Text(node.localizedName(lang),
-                      style: PangolinText.sm
-                          .copyWith(color: c.fg1, fontWeight: FontWeight.w600, fontSize: 15)),
-                  const SizedBox(height: 2),
-                  Text(node.localizedSub(lang),
-                      style: PangolinText.caption.copyWith(color: c.fg3, fontWeight: FontWeight.w400)),
-                ],
+      onTap: down ? null : onTap,
+      child: Opacity(
+        opacity: down ? 0.55 : 1.0,
+        child: Container(
+          color: (active && !down) ? c.accentSubtle : Colors.transparent,
+          padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 12),
+          child: Row(
+            children: [
+              CountryCode(code: node.code, active: active && !down),
+              const SizedBox(width: 13),
+              Expanded(
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    Text(node.localizedName(lang),
+                        style: PangolinText.sm
+                            .copyWith(color: c.fg1, fontWeight: FontWeight.w600, fontSize: 15)),
+                    const SizedBox(height: 2),
+                    Text(node.localizedSub(lang),
+                        style: PangolinText.caption.copyWith(color: c.fg3, fontWeight: FontWeight.w400)),
+                  ],
+                ),
               ),
-            ),
-            Text(node.pingLabel, style: PangolinText.mono.copyWith(color: c.fg2, fontSize: 12)),
-            const SizedBox(width: 8),
-            SignalBars(ping: node.ping),
-            if (active) ...[const SizedBox(width: 10), Icon(PangolinIcons.check, size: 18, color: c.accent)],
-          ],
+              if (down)
+                Text(unavail,
+                    style: PangolinText.caption.copyWith(color: c.danger, fontWeight: FontWeight.w600, fontSize: 12))
+              else ...[
+                Text(node.pingLabel, style: PangolinText.mono.copyWith(color: c.fg2, fontSize: 12)),
+                const SizedBox(width: 8),
+                SignalBars(ping: node.ping),
+                if (active) ...[const SizedBox(width: 10), Icon(PangolinIcons.check, size: 18, color: c.accent)],
+              ],
+            ],
+          ),
         ),
       ),
     );

client/test/widget/server_tile_down_test.dart

@@ -0,0 +1,43 @@
+// server_tile_down_test.dart — 节点不可用(status!=up)的列表项渲染断言。
+// 锁住 #7 客户端侧:agent 离线 → 节点显示「不可用」+ 禁选(onTap 不触发)。
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pangolin_vpn/l10n/app_text.dart';
+import 'package:pangolin_vpn/models/node.dart';
+import 'package:pangolin_vpn/pangolin_theme.dart';
+import 'package:pangolin_vpn/widgets/server_tile.dart';
+
+import '../helpers/harness.dart';
+
+void main() {
+  setUpAll(disableGoogleFontsFetching);
+
+  Widget wrap(Node node, VoidCallback onTap) => MaterialApp(
+        theme: PangolinTheme.light,
+        home: Scaffold(body: ServerTile(node: node, lang: AppLang.zh, onTap: onTap)),
+      );
+
+  testWidgets('节点 down → 显示「不可用」且点击不触发', (t) async {
+    var tapped = false;
+    await t.pumpWidget(wrap(
+      const Node(code: 'US', nameZh: '洛杉矶', nameEn: 'LA', ping: 30, status: 'down'),
+      () => tapped = true,
+    ));
+    expect(find.text('不可用'), findsOneWidget);
+    await t.tap(find.byType(ServerTile));
+    await t.pump();
+    expect(tapped, isFalse, reason: 'down 节点禁选,onTap 不触发');
+  });
+
+  testWidgets('节点 up → 不显示「不可用」,点击正常触发', (t) async {
+    var tapped = false;
+    await t.pumpWidget(wrap(
+      const Node(code: 'US', nameZh: '洛杉矶', nameEn: 'LA', ping: 30), // status 默认 up
+      () => tapped = true,
+    ));
+    expect(find.text('不可用'), findsNothing);
+    await t.tap(find.byType(ServerTile));
+    await t.pump();
+    expect(tapped, isTrue);
+  });
+}