feat: 实时消息与管理端运营能力

新增群聊/私信与公共 WebSocket 总线，站长用户内容档案，并将通知与待审角标改为推送驱动；同步精简管理仪表盘并修复主题换肤 DOM 冲突。

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/components/ConfirmDialog.tsx

@@ -0,0 +1,84 @@
+"use client";
+
+import { X } from "lucide-react";
+
+/**
+ * 站点风格确认框：仅取消/关闭可关，避免点遮罩误关。
+ * danger 主按钮使用 btn-danger，其余用 btn-accent。
+ */
+export default function ConfirmDialog({
+  open,
+  title,
+  message,
+  confirmLabel = "确定",
+  cancelLabel = "取消",
+  danger = false,
+  busy = false,
+  onConfirm,
+  onCancel,
+}: {
+  open: boolean;
+  title: string;
+  message: string;
+  confirmLabel?: string;
+  cancelLabel?: string;
+  danger?: boolean;
+  busy?: boolean;
+  onConfirm: () => void;
+  onCancel: () => void;
+}) {
+  if (!open) return null;
+
+  return (
+    <div
+      className="fixed inset-0 z-[1100] flex items-center justify-center p-4"
+      style={{ background: "rgba(0,0,0,0.55)" }}
+    >
+      <div
+        className="w-full max-w-sm rounded-2xl p-5 j13-toast-in"
+        style={{ background: "var(--panel)", border: "1px solid var(--line)" }}
+        onClick={(e) => e.stopPropagation()}
+      >
+        <div className="flex items-start justify-between gap-3 mb-3">
+          <h2
+            className="text-[16px] font-extrabold leading-snug"
+            style={{ color: "var(--ink)" }}
+          >
+            {title}
+          </h2>
+          <button
+            type="button"
+            onClick={onCancel}
+            disabled={busy}
+            aria-label="关闭"
+            className="w-7 h-7 shrink-0 flex items-center justify-center rounded-full hover:bg-[var(--accent-soft)] transition-colors"
+            style={{ color: "var(--ink-3)" }}
+          >
+            <X size={15} />
+          </button>
+        </div>
+        <p className="text-[13.5px] leading-relaxed mb-5" style={{ color: "var(--ink-2)" }}>
+          {message}
+        </p>
+        <div className="flex justify-end gap-2">
+          <button
+            type="button"
+            onClick={onCancel}
+            disabled={busy}
+            className="btn btn-line btn-sm"
+          >
+            {cancelLabel}
+          </button>
+          <button
+            type="button"
+            onClick={onConfirm}
+            disabled={busy}
+            className={`btn btn-sm ${danger ? "btn-danger" : "btn-accent"}`}
+          >
+            {busy ? "处理中…" : confirmLabel}
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}