fix(web): 离线/内网环境改用系统字体，避免构建时联网下载 Google 字体

apps/web/src/app/globals.css

@@ -4,6 +4,16 @@
 
 @custom-variant dark (&:is(.dark *));
 
+/* 系统字体回退：离线/内网环境不依赖 Google 字体 */
+:root {
+  --font-sans: ui-sans-serif, system-ui, -apple-system, "PingFang SC",
+    "Microsoft YaHei", "Hiragino Sans GB", "Segoe UI", Roboto, Helvetica, Arial,
+    sans-serif;
+  --font-geist-sans: var(--font-sans);
+  --font-geist-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
+    "Liberation Mono", monospace;
+}
+
 @theme inline {
   --color-background: var(--background);
   --color-foreground: var(--foreground);

apps/web/src/app/layout.tsx

@@ -1,18 +1,16 @@
 import type { Metadata } from "next";
-import { Geist, Geist_Mono } from "next/font/google";
 import { Providers } from "@/components/providers";
 import { Toaster } from "@/components/ui/sonner";
 import "./globals.css";
 
-const geistSans = Geist({
+// 使用系统字体，避免构建时联网下载 Google 字体（内网/离线环境）
+const geistSans = {
   variable: "--font-geist-sans",
-  subsets: ["latin"],
-});
+};
 
-const geistMono = Geist_Mono({
+const geistMono = {
   variable: "--font-geist-mono",
-  subsets: ["latin"],
-});
+};
 
 export const metadata: Metadata = {
   title: "AI智能应用平台",