feat(ui): add responsive mobile header and footer components

- Implemented `MobileHeader` with support for displaying unread messages.
- Created `MobileFooter` with navigation to key sections (home, explore, publish, trends, profile).
- Replaced legacy mobile header with new `MobileHeader` and `MobileFooter` in the dashboard layout.
- Optimized mobile sidebar rendering for improved responsiveness.

frontend/src/app/(dashboard)/layout.tsx

@@ -1,15 +1,11 @@
 import * as React from "react";
 import { AppSidebar } from "@/components/app-sidebar";
 import { MobileFilters } from "@/components/mobile-filters";
-import { ModeToggle } from "@/components/mode-toggle";
+import { MobileFooter } from "@/components/mobile-footer";
+import { MobileHeader } from "@/components/mobile-header";
 import { SearchSidebar } from "@/components/search-sidebar";
-import {
-	SidebarInset,
-	SidebarProvider,
-	SidebarTrigger,
-} from "@/components/ui/sidebar";
+import { SidebarInset, SidebarProvider } from "@/components/ui/sidebar";
 import { Toaster } from "@/components/ui/sonner";
-import { UserNavMobile } from "@/components/user-nav-mobile";
 
 export default function DashboardLayout({
 	children,
@@ -22,20 +18,9 @@ export default function DashboardLayout({
 		<React.Suspense fallback={null}>
 			<SidebarProvider>
 				<AppSidebar />
-				<SidebarInset className="flex flex-row overflow-hidden">
+				<SidebarInset className="flex flex-row overflow-hidden pb-16 lg:pb-0">
 					<div className="flex-1 flex flex-col min-w-0">
-						<header className="flex h-16 shrink-0 items-center gap-2 border-b px-4 lg:hidden sticky top-0 bg-background z-40">
-							<SidebarTrigger />
-							<div className="flex-1 flex justify-center">
-								<span className="font-bold text-primary text-xl tracking-tight">
-									MemeGoat
-								</span>
-							</div>
-							<div className="flex items-center gap-2">
-								<ModeToggle />
-								<UserNavMobile />
-							</div>
-						</header>
+						<MobileHeader />
 						<main className="flex-1 overflow-y-auto bg-zinc-50 dark:bg-zinc-950">
 							{children}
 							{modal}
@@ -43,6 +28,7 @@ export default function DashboardLayout({
 						<React.Suspense fallback={null}>
 							<MobileFilters />
 						</React.Suspense>
+						<MobileFooter />
 					</div>
 					<React.Suspense fallback={null}>
 						<SearchSidebar />

frontend/src/app/(dashboard)/profile/page.tsx

@@ -3,16 +3,19 @@
 import {
 	Calendar,
 	Camera,
+	HelpCircle,
 	LogIn,
 	LogOut,
 	Settings,
 	Share2,
+	ShieldCheck,
 } from "lucide-react";
 import Link from "next/link";
 import { useSearchParams } from "next/navigation";
 import * as React from "react";
 import { toast } from "sonner";
 import { ContentList } from "@/components/content-list";
+import { ModeToggle } from "@/components/mode-toggle";
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
 import { Button } from "@/components/ui/button";
 import {
@@ -157,6 +160,19 @@ export default function ProfilePage() {
 						</div>
 
 						<div className="flex flex-wrap justify-center md:justify-start gap-2 pt-2">
+							{user.role === "admin" && (
+								<Button
+									asChild
+									variant="outline"
+									size="sm"
+									className="h-9 px-4 border-primary/20 hover:bg-primary/5 text-primary"
+								>
+									<Link href="/admin">
+										<ShieldCheck className="h-4 w-4 mr-2" />
+										Administration
+									</Link>
+								</Button>
+							)}
 							<Button asChild variant="outline" size="sm" className="h-9 px-4">
 								<Link href="/settings">
 									<Settings className="h-4 w-4 mr-2" />
@@ -181,6 +197,14 @@ export default function ProfilePage() {
 								<LogOut className="h-4 w-4 mr-2" />
 								Déconnexion
 							</Button>
+
+							<Button asChild variant="outline" size="sm" className="h-9 px-4">
+								<Link href="/help">
+									<HelpCircle className="h-4 w-4 mr-2" />
+									Aide
+								</Link>
+							</Button>
+							<ModeToggle />
 						</div>
 					</div>
 				</div>

frontend/src/components/app-sidebar.tsx

@@ -54,6 +54,7 @@ import {
 	SidebarRail,
 	SidebarTrigger,
 } from "@/components/ui/sidebar";
+import { useIsMobile } from "@/hooks/use-mobile";
 import { useAuth } from "@/providers/auth-provider";
 import { useSocket } from "@/providers/socket-provider";
 import { CategoryService } from "@/services/category.service";
@@ -79,6 +80,7 @@ const mainNav = [
 ];
 
 export function AppSidebar() {
+	const isMobile = useIsMobile();
 	const pathname = usePathname();
 	const searchParams = useSearchParams();
 	const { user, logout, isAuthenticated } = useAuth();
@@ -129,6 +131,8 @@ export function AppSidebar() {
 			: "/memegoat-black.svg";
 	}, [resolvedTheme, mounted]);
 
+	if (isMobile) return null;
+
 	return (
 		<Sidebar collapsible="icon">
 			<SidebarHeader className="flex flex-row items-center justify-between py-4 group-data-[collapsible=icon]:justify-center">

frontend/src/components/mobile-filters.tsx

@@ -1,10 +1,9 @@
 "use client";
 
-import { Filter, Search } from "lucide-react";
+import { Search } from "lucide-react";
 import { usePathname, useRouter, useSearchParams } from "next/navigation";
 import * as React from "react";
 import { Badge } from "@/components/ui/badge";
-import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { ScrollArea } from "@/components/ui/scroll-area";
 import { Separator } from "@/components/ui/separator";
@@ -13,7 +12,6 @@ import {
 	SheetContent,
 	SheetHeader,
 	SheetTitle,
-	SheetTrigger,
 } from "@/components/ui/sheet";
 import { CategoryService } from "@/services/category.service";
 import { TagService } from "@/services/tag.service";
@@ -29,6 +27,16 @@ export function MobileFilters() {
 	const [query, setQuery] = React.useState(searchParams.get("query") || "");
 	const [open, setOpen] = React.useState(false);
 
+	React.useEffect(() => {
+		if (searchParams.get("openSearch") === "true") {
+			setOpen(true);
+			// Nettoyer l'URL sans recharger
+			const params = new URLSearchParams(searchParams.toString());
+			params.delete("openSearch");
+			router.replace(`${pathname}?${params.toString()}`, { scroll: false });
+		}
+	}, [searchParams, pathname, router]);
+
 	React.useEffect(() => {
 		if (open) {
 			CategoryService.getAll().then(setCategories).catch(console.error);
@@ -61,13 +69,8 @@ export function MobileFilters() {
 	const currentCategory = searchParams.get("category");
 
 	return (
-		<div className="lg:hidden fixed top-4 right-4 z-50">
+		<div className="lg:hidden">
 			<Sheet open={open} onOpenChange={setOpen}>
-				<SheetTrigger asChild>
-					<Button size="icon" className="rounded-full shadow-lg h-12 w-12">
-						<Filter className="h-6 w-6" />
-					</Button>
-				</SheetTrigger>
 				<SheetContent side="right" className="w-[300px] sm:w-[400px]">
 					<SheetHeader>
 						<SheetTitle>Recherche & Filtres</SheetTitle>

frontend/src/components/mobile-footer.tsx

@@ -0,0 +1,80 @@
+"use client";
+
+import { Home, PlusCircle, Search, TrendingUp, User } from "lucide-react";
+import Link from "next/link";
+import { usePathname } from "next/navigation";
+import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
+import { cn } from "@/lib/utils";
+import { useAuth } from "@/providers/auth-provider";
+
+export function MobileFooter() {
+	const pathname = usePathname();
+	const { user, isAuthenticated } = useAuth();
+
+	const navItems = [
+		{
+			title: "Accueil",
+			url: "/",
+			icon: Home,
+		},
+		{
+			title: "Explorer",
+			url: "/trends?openSearch=true",
+			icon: Search,
+		},
+		{
+			title: "Publier",
+			url: "/upload",
+			icon: PlusCircle,
+		},
+		{
+			title: "Tendances",
+			url: "/trends",
+			icon: TrendingUp,
+		},
+		{
+			title: "Profil",
+			url: "/profile",
+			icon: User,
+		},
+	];
+
+	return (
+		<footer className="lg:hidden fixed bottom-0 left-0 right-0 border-t bg-background z-40 h-16">
+			<nav className="flex h-full items-center justify-around px-2">
+				{navItems.map((item) => {
+					const isActive = pathname === item.url.split("?")[0];
+					const isProfile = item.title === "Profil";
+
+					return (
+						<Link
+							key={item.url}
+							href={item.url}
+							className={cn(
+								"flex flex-1 flex-col items-center justify-center gap-1 transition-colors min-h-[44px]",
+								isActive ? "text-primary" : "text-muted-foreground hover:text-primary",
+							)}
+						>
+							{isProfile && isAuthenticated && user ? (
+								<Avatar
+									className={cn(
+										"h-6 w-6 border",
+										isActive && "ring-2 ring-primary ring-offset-2",
+									)}
+								>
+									<AvatarImage src={user.avatarUrl} alt={user.username} />
+									<AvatarFallback className="text-[8px]">
+										{user.username.slice(0, 2).toUpperCase()}
+									</AvatarFallback>
+								</Avatar>
+							) : (
+								<item.icon className={cn("h-6 w-6", isActive && "fill-current")} />
+							)}
+							<span className="text-[10px] font-medium">{item.title}</span>
+						</Link>
+					);
+				})}
+			</nav>
+		</footer>
+	);
+}

frontend/src/components/mobile-header.tsx

@@ -0,0 +1,66 @@
+"use client";
+
+import { MessageCircle } from "lucide-react";
+import Link from "next/link";
+import { usePathname } from "next/navigation";
+import * as React from "react";
+import { Button } from "@/components/ui/button";
+import { useAuth } from "@/providers/auth-provider";
+import { useSocket } from "@/providers/socket-provider";
+import { MessageService } from "@/services/message.service";
+
+export function MobileHeader() {
+	const pathname = usePathname();
+	const { isAuthenticated } = useAuth();
+	const { socket } = useSocket();
+	const [unreadMessages, setUnreadMessages] = React.useState(0);
+
+	React.useEffect(() => {
+		if (isAuthenticated) {
+			MessageService.getUnreadCount().then(setUnreadMessages).catch(console.error);
+		}
+	}, [isAuthenticated]);
+
+	React.useEffect(() => {
+		if (socket && isAuthenticated) {
+			const handleNewMessage = () => {
+				if (pathname !== "/messages") {
+					setUnreadMessages((prev) => prev + 1);
+				}
+			};
+			socket.on("new_message", handleNewMessage);
+			return () => {
+				socket.off("new_message", handleNewMessage);
+			};
+		}
+	}, [socket, isAuthenticated, pathname]);
+
+	React.useEffect(() => {
+		if (pathname === "/messages") {
+			setUnreadMessages(0);
+		}
+	}, [pathname]);
+
+	return (
+		<header className="flex h-16 shrink-0 items-center justify-between border-b px-4 lg:hidden sticky top-0 bg-background z-40">
+			<Link href="/" className="flex items-center gap-2">
+				<span className="font-bold text-primary text-xl tracking-tight">
+					MemeGoat
+				</span>
+			</Link>
+
+			<div className="flex items-center gap-2">
+				<Button variant="ghost" size="icon" asChild className="h-9 w-9 relative">
+					<Link href="/messages">
+						<MessageCircle className="h-5 w-5" />
+						{unreadMessages > 0 && (
+							<span className="absolute top-1 right-1 flex h-4 w-4 items-center justify-center rounded-full bg-red-500 text-[10px] text-white">
+								{unreadMessages > 9 ? "9+" : unreadMessages}
+							</span>
+						)}
+					</Link>
+				</Button>
+			</div>
+		</header>
+	);
+}