feat: add comments functionality and integrate Socket.io for real-time updates

- Implemented a full comments module in the backend with repository, service, controller, and DTOs using NestJS.
- Added frontend support for comments with a `CommentSection` component and integration into content pages.
- Introduced `SocketProvider` on the frontend and integrated Socket.io for real-time communication.
- Updated dependencies and configurations for Socket.io and WebSockets support.

frontend/src/components/app-sidebar.tsx

@@ -10,6 +10,7 @@ import {
 	LayoutGrid,
 	LogIn,
 	LogOut,
+	MessageCircle,
 	PlusCircle,
 	Settings,
 	ShieldCheck,
@@ -180,6 +181,20 @@ export function AppSidebar() {
 								</Link>
 							</SidebarMenuButton>
 						</SidebarMenuItem>
+						{isAuthenticated && (
+							<SidebarMenuItem>
+								<SidebarMenuButton
+									asChild
+									isActive={pathname === "/messages"}
+									tooltip="Messages"
+								>
+									<Link href="/messages">
+										<MessageCircle />
+										<span>Messages</span>
+									</Link>
+								</SidebarMenuButton>
+							</SidebarMenuItem>
+						)}
 					</SidebarMenu>
 				</SidebarGroup>