feat: add forum seed categories, improve page layouts and navigation

- Seed default forum categories (announcements, learning, feedback) on startup
- Update forum pages with improved category/post/reply UI
- Refine navbar, mobile nav, and home page content layout
- Improve analytics, course-content, knowledge, profile, settings, spatial pages

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/src/components/home/home-page-content.tsx

@@ -38,7 +38,7 @@ const modules = [
     visual: "spatial" as const,
   },
   {
-    title: "论坛社区",
+    title: "课程社区",
     description: "课程讨论与学习经验交流平台，促进师生互动与同伴学习",
     href: "/forum",
     tags: ["协作"],
@@ -436,20 +436,12 @@ export default function HomePageContent() {
                 <p className="text-sm text-muted-foreground leading-relaxed mb-5">
                   基于先进AI技术的国土空间规划智能学习平台，集成RAG检索增强生成、图像生成、数据分析等能力，为专业教学与研究提供全方位支持。
                 </p>
-                <div className="flex gap-3">
-                  <Button asChild variant="outline" size="sm">
-                    <a href="https://tsp.spacekg.com/#/" target="_blank" rel="noopener noreferrer">
-                      <BookOpen className="mr-2 h-4 w-4" />
-                      课题组主页
-                    </a>
-                  </Button>
-                  <Button asChild variant="outline" size="sm">
-                    <a href="https://homepage.hit.edu.cn/wusongtao" target="_blank" rel="noopener noreferrer">
-                      <Users className="mr-2 h-4 w-4" />
-                      联系我们
-                    </a>
-                  </Button>
-                </div>
+                <Button asChild variant="outline" size="sm">
+                  <a href="https://homepage.hit.edu.cn/wusongtao" target="_blank" rel="noopener noreferrer">
+                    <Users className="mr-2 h-4 w-4" />
+                    联系我们
+                  </a>
+                </Button>
               </div>
 
               {/* 快速链接 */}
@@ -463,16 +455,6 @@ export default function HomePageContent() {
                       </Link>
                     </li>
                   ))}
-                  <li>
-                    <Link href="/analytics" className="text-sm text-muted-foreground hover:text-foreground transition-colors">
-                      学习进度
-                    </Link>
-                  </li>
-                  <li>
-                    <Link href="/settings" className="text-sm text-muted-foreground hover:text-foreground transition-colors">
-                      系统设置
-                    </Link>
-                  </li>
                 </ul>
               </div>
 

web/src/components/home/navbar.tsx

@@ -1,12 +1,13 @@
 "use client";
 
 import Link from "next/link";
+import { usePathname } from "next/navigation";
 import { Button } from "@/components/ui/button";
 import { Avatar, AvatarFallback } from "@/components/ui/avatar";
 import { ThemeToggle } from "@/components/ui/theme-toggle";
 import { DropdownMenu, DropdownMenuContent, DropdownMenuItem, DropdownMenuSeparator, DropdownMenuTrigger } from "@/components/ui/dropdown-menu";
 import { useAuthStore } from "@/store/auth";
-import { BookOpen, LogOut, User as UserIcon, Settings, ChevronDown, MessageSquare, Database, Image, TrendingUp, GraduationCap } from "lucide-react";
+import { BookOpen, LogOut, User as UserIcon, Settings, ChevronDown, MessageSquare, Database, Image, TrendingUp, GraduationCap, Users } from "lucide-react";
 import { User } from "@/types";
 
 interface NavbarProps {
@@ -14,14 +15,28 @@ interface NavbarProps {
   user: User | null;
 }
 
+const NAV_LINKS = [
+  { href: "/course-content", label: "课程内容", icon: GraduationCap },
+  { href: "/chat", label: "智能问答", icon: MessageSquare },
+  { href: "/knowledge", label: "知识库", icon: Database },
+  { href: "/spatial", label: "空间设计", icon: Image },
+  { href: "/forum", label: "课程社区", icon: Users },
+];
+
 export default function Navbar({ isAuthenticated, user }: NavbarProps) {
   const { logout } = useAuthStore();
+  const pathname = usePathname();
+
+  const isActive = (href: string) => {
+    if (href === "/forum") return pathname === "/forum" || pathname.startsWith("/forum/");
+    return pathname === href || pathname.startsWith(href + "/");
+  };
 
   return (
     <nav className="border-b bg-background/95 backdrop-blur-sm sticky top-0 z-50">
       <div className="mit-container">
         <div className="flex justify-between items-center h-16">
-          {/* Logo 和标题 */}
+          {/* Logo */}
           <Link href="/" className="flex items-center space-x-3 hover:opacity-80 transition-opacity cursor-pointer">
             <div className="w-10 h-10 bg-primary rounded-lg flex items-center justify-center shadow-sm">
               <BookOpen className="w-6 h-6 text-white" />
@@ -36,46 +51,60 @@ export default function Navbar({ isAuthenticated, user }: NavbarProps) {
             </div>
           </Link>
 
-          {/* 导航链接 */}
+          {/* 导航链接 — 带底部下划线指示 */}
           {isAuthenticated && (
-            <div className="hidden md:flex items-center space-x-1">
-              <Link href="/course-content">
-                <Button variant="ghost" className="flex items-center space-x-2 px-3 py-2 hover:bg-muted/50">
-                  <GraduationCap className="w-4 h-4" />
-                  <span className="text-sm">课程内容</span>
-                </Button>
-              </Link>
-              <Link href="/chat">
-                <Button variant="ghost" className="flex items-center space-x-2 px-3 py-2 hover:bg-muted/50">
-                  <MessageSquare className="w-4 h-4" />
-                  <span className="text-sm">智能问答</span>
-                </Button>
-              </Link>
-              <Link href="/knowledge">
-                <Button variant="ghost" className="flex items-center space-x-2 px-3 py-2 hover:bg-muted/50">
-                  <Database className="w-4 h-4" />
-                  <span className="text-sm">知识库</span>
-                </Button>
-              </Link>
-              <Link href="/spatial">
-                <Button variant="ghost" className="flex items-center space-x-2 px-3 py-2 hover:bg-muted/50">
-                  <Image className="w-4 h-4" />
-                  <span className="text-sm">空间设计</span>
-                </Button>
+            <div className="hidden md:flex items-center h-full -mb-px">
+              {NAV_LINKS.map((item) => {
+                const active = isActive(item.href);
+                return (
+                  <Link
+                    key={item.href}
+                    href={item.href}
+                    className={`
+                      relative flex items-center gap-1.5 px-3 h-full text-sm transition-colors
+                      ${active
+                        ? "text-primary font-medium"
+                        : "text-muted-foreground hover:text-foreground"
+                      }
+                    `}
+                  >
+                    <item.icon className="w-4 h-4" />
+                    <span>{item.label}</span>
+                    {active && (
+                      <span className="absolute bottom-0 left-3 right-3 h-0.5 bg-primary rounded-full" />
+                    )}
+                  </Link>
+                );
+              })}
+            </div>
+          )}
+
+          {/* 未登录时也显示课程社区链接 */}
+          {!isAuthenticated && (
+            <div className="hidden md:flex items-center h-full -mb-px">
+              <Link
+                href="/forum"
+                className={`
+                  relative flex items-center gap-1.5 px-3 h-full text-sm transition-colors
+                  ${isActive("/forum")
+                    ? "text-primary font-medium"
+                    : "text-muted-foreground hover:text-foreground"
+                  }
+                `}
+              >
+                <Users className="w-4 h-4" />
+                <span>课程社区</span>
+                {isActive("/forum") && (
+                  <span className="absolute bottom-0 left-3 right-3 h-0.5 bg-primary rounded-full" />
+                )}
               </Link>
             </div>
           )}
 
           <div className="flex items-center space-x-3">
             <ThemeToggle />
-            <Link href="/forum">
-              <Button variant="outline" size="sm">
-                课程社区
-              </Button>
-            </Link>
 
             {isAuthenticated && user ? (
-              // 登录后状态 - 用户下拉菜单
               <DropdownMenu>
                 <DropdownMenuTrigger asChild>
                   <Button variant="ghost" className="flex items-center space-x-2 px-3 hover:bg-muted/50">
@@ -127,7 +156,6 @@ export default function Navbar({ isAuthenticated, user }: NavbarProps) {
                 </DropdownMenuContent>
               </DropdownMenu>
             ) : (
-              // 未登录状态
               <div className="flex items-center space-x-2">
                 <Button variant="ghost" asChild>
                   <Link href="/login">登录</Link>

web/src/components/layout/mobile-nav.tsx

@@ -4,17 +4,18 @@ import { useState } from "react";
 import { useRouter, usePathname } from "next/navigation";
 import { useAuthStore } from "@/store/auth";
 import { Button } from "@/components/ui/button";
-import { 
-  MessageSquare, 
-  BookOpen, 
-  Image, 
+import {
+  MessageSquare,
+  BookOpen,
+  Image,
   Settings,
   Menu,
   X,
   User,
   LogOut,
   GraduationCap,
-  TrendingUp
+  TrendingUp,
+  Users
 } from "lucide-react";
 
 const navItems = [
@@ -22,6 +23,7 @@ const navItems = [
   { id: "chat", name: "对话", icon: MessageSquare, href: "/chat" },
   { id: "knowledge", name: "知识库", icon: BookOpen, href: "/knowledge" },
   { id: "spatial", name: "空间出图", icon: Image, href: "/spatial" },
+  { id: "forum", name: "社区", icon: Users, href: "/forum" },
 ];
 
 export default function MobileNav() {