fix: source list scroll, citation targeting, and page UI polish

- Replace ScrollArea with native overflow-y-auto for reliable mouse wheel scrolling
- Scope source DOM IDs by message ID to fix cross-round citation jumps
- Improve profile, settings, forum, knowledge page layouts
- Update mobile navigation and chat interface

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

web/src/app/(auth)/login/page.tsx

@@ -76,7 +76,7 @@ export default function LoginPage() {
               href="/" 
               className="flex items-center justify-center space-x-3 mb-6 group cursor-pointer transition-opacity hover:opacity-80"
             >
-              <div className="w-12 h-12 bg-gradient-to-r from-blue-500 to-purple-600 rounded-xl flex items-center justify-center shadow-lg group-hover:shadow-xl transition-shadow">
+              <div className="w-12 h-12 bg-primary rounded-xl flex items-center justify-center shadow-md group-hover:shadow-lg transition-shadow">
                 <BookOpen className="w-7 h-7 text-white" />
               </div>
               <span className="text-2xl font-bold">