feat: 🛡️ Sentinel 集群监控插件 + API Key 系统 + 框架设置页

== API Key 系统 ==
- services/web_panel/routes/apikeys.py: CRUD + 权限模板 + 过期控制
- panel_auth + _check_plugin_auth 双重验证 (Session → API Key)
- 模板: readonly(只读) / monitor(监控) / full(管理)
- 持久化到 SenSuDB + 过期自动清理

== WebUI 框架设置页 ==
- static/web_panel/pages/settings.html: API Key 管理界面
- 创建对话框 (名称/权限/TTL), 列表表格, 一键删除

== 热重载修复 ==
- PluginService._reload_plugin: 路由器冻结时跳过 (避免破坏已注册路由)

== 🛡️ Sentinel 插件 ==
- 多节点 SenSu 集群性能监控
- 后台 urllib+run_in_executor 轮询 (避免事件循环死锁)
- SSE 实时推送仪表盘
- 节点管理页 (增删改+连接测试+备注)
- 路径: /sentinel/api/nodes

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

plugins/sentinel/dashboard.html

@@ -0,0 +1,91 @@
+<div class="plugin-page-root" style="padding:16px">
+  <div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:16px">
+    <h2 style="margin:0">🛡️ Sentinel 集群监控</h2>
+    <span id="sentinel-status" style="font-size:.8rem;color:var(--text-dim)">连接中...</span>
+  </div>
+  <div id="sentinel-grid" style="display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:12px">
+    <div class="card" style="text-align:center;padding:24px;color:var(--text-dim)">加载中...</div>
+  </div>
+
+  <style>
+    .node-card { background:var(--md-sys-color-surface-container); border-radius:var(--shape-sm); padding:16px; transition:box-shadow .2s }
+    .node-card:hover { box-shadow:0 2px 8px rgba(0,0,0,.2) }
+    .node-card.online { border-left:3px solid var(--success, #4caf50) }
+    .node-card.offline { border-left:3px solid var(--error, #f44336); opacity:.7 }
+    .node-name { font-weight:600; font-size:1rem; margin-bottom:4px }
+    .node-url { font-size:.75rem; color:var(--text-dim); margin-bottom:12px; word-break:break-all }
+    .metric-row { display:flex; gap:12px; margin-bottom:8px }
+    .metric { flex:1 }
+    .metric-label { font-size:.7rem; color:var(--text-dim); text-transform:uppercase }
+    .metric-value { font-size:1.1rem; font-weight:600 }
+    .metric-bar { height:4px; border-radius:2px; margin-top:2px; background:var(--md-sys-color-surface-container-lowest) }
+    .metric-bar-fill { height:100%; border-radius:2px; transition:width .5s }
+    .bar-green { background:#4caf50 } .bar-yellow { background:#ff9800 } .bar-red { background:#f44336 }
+  </style>
+
+  <script>
+    var sseConn = null;
+    var currentNodes = [];
+
+    function renderNodes(nodes) {
+      currentNodes = nodes || [];
+      var grid = document.getElementById("sentinel-grid");
+      document.getElementById("sentinel-status").textContent =
+        "在线 " + nodes.filter(function(n){return n.online}).length + "/" + nodes.length;
+
+      if (!nodes.length) {
+        grid.innerHTML = '<div class="card" style="text-align:center;padding:24px;color:var(--text-dim)">暂无节点 — 在节点管理中添加</div>';
+        return;
+      }
+
+      grid.innerHTML = nodes.map(function(n){
+        var sys = n.system || {};
+        var cpu = sys.cpu || {};
+        var mem = sys.memory || {};
+        var net = sys.net_speed || {};
+        var cls = n.online ? 'online' : 'offline';
+        var cpuBar = bar(cpu.percent||0);
+        var memBar = bar(mem.percent||0);
+
+        return '<div class="node-card '+cls+'">'+
+          '<div class="node-name">'+(n.online?'🟢':'🔴')+' '+esc(n.name)+'</div>'+
+          '<div class="node-url">'+esc(n.url)+'</div>'+
+          (n.notes ? '<div style="font-size:.75rem;color:var(--text-dim);margin-bottom:8px;font-style:italic">📝 '+esc(n.notes)+'</div>' : '')+
+          (n.online ?
+            '<div class="metric-row">'+
+              '<div class="metric"><div class="metric-label">CPU</div><div class="metric-value">'+(cpu.percent||0).toFixed(1)+'%</div><div class="metric-bar"><div class="metric-bar-fill '+cpuBar+'" style="width:'+(cpu.percent||0)+'%"></div></div></div>'+
+              '<div class="metric"><div class="metric-label">MEM</div><div class="metric-value">'+(mem.percent||0).toFixed(1)+'%</div><div class="metric-bar"><div class="metric-bar-fill '+memBar+'" style="width:'+(mem.percent||0)+'%"></div></div></div>'+
+            '</div>'+
+            '<div class="metric-row">'+
+              '<div class="metric"><div class="metric-label">NET ↓</div><div class="metric-value" style="font-size:.9rem">'+fmtSpeed(net.rx_bytes_sec||0)+'</div></div>'+
+              '<div class="metric"><div class="metric-label">NET ↑</div><div class="metric-value" style="font-size:.9rem">'+fmtSpeed(net.tx_bytes_sec||0)+'</div></div>'+
+            '</div>'+
+            '<div style="font-size:.7rem;color:var(--text-dim);margin-top:8px">内存 '+(mem.used_gb||0).toFixed(1)+'/'+(mem.total_gb||0).toFixed(1)+' GB</div>'
+          : '<div style="color:var(--error);font-size:.85rem">'+(n.error||'离线')+'</div>')+
+          '<div style="font-size:.7rem;color:var(--text-dim);margin-top:8px">'+(n.last_seen ? new Date(n.last_seen*1000).toLocaleTimeString() : '—')+'</div>'+
+        '</div>';
+      }).join("");
+    }
+
+    function bar(v) { return v < 60 ? 'bar-green' : (v < 85 ? 'bar-yellow' : 'bar-red'); }
+    function fmtSpeed(bps) { return bps<1024?bps.toFixed(0)+'B/s':(bps<1048576?(bps/1024).toFixed(0)+'K/s':(bps/1048576).toFixed(1)+'M/s'); }
+    function esc(s) { return String(s).replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;'); }
+
+    // ── SSE ──
+    function connectSSE() {
+      if (sseConn) { sseConn.close(); sseConn = null; }
+      sseConn = new EventSource("/SenSu/plugin/sentinel/sse");
+      sseConn.addEventListener("nodes_update", function(e){
+        var d = JSON.parse(e.data);
+        if (d.nodes) renderNodes(d.nodes);
+      });
+      sseConn.onerror = function(){ setTimeout(connectSSE, 5000); };
+    }
+
+    // ── 初始加载 ──
+    fetch("/sentinel/api/nodes").then(function(r){return r.json()}).then(function(d){
+      if (d.nodes) renderNodes(d.nodes);
+    }).catch(function(){});
+    connectSSE();
+  </script>
+</div>