feat: add authentication support and user model

- Updated `env.example` to include NextAuth configuration for authentication.
- Added `next-auth` dependency to manage user sessions.
- Introduced `User` model in Prisma schema with fields for user details and password hashing.
- Integrated `AuthProvider` in layout for session management across the app.
- Enhanced `Header` component with `AuthButton` for user authentication controls.

src/components/AuthButton.tsx

@@ -0,0 +1,56 @@
+'use client'
+
+import { useSession, signOut } from 'next-auth/react'
+import { useRouter } from 'next/navigation'
+import { Button } from '@/components/ui/Button'
+
+export function AuthButton() {
+  const { data: session, status } = useSession()
+  const router = useRouter()
+
+  if (status === 'loading') {
+    return (
+      <div className="text-[var(--muted-foreground)] text-sm">
+        Chargement...
+      </div>
+    )
+  }
+
+  if (!session) {
+    return (
+      <Button
+        onClick={() => router.push('/login')}
+        size="sm"
+      >
+        Se connecter
+      </Button>
+    )
+  }
+
+  return (
+    <div className="flex items-center gap-1">
+      <Button
+        onClick={() => router.push('/profile')}
+        variant="ghost"
+        size="sm"
+        className="p-1 h-auto"
+        title={`Profil - ${session.user?.email}`}
+      >
+        <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M16 7a4 4 0 11-8 0 4 4 0 018 0zM12 14a7 7 0 00-7 7h14a7 7 0 00-7-7z" />
+        </svg>
+      </Button>
+      <Button
+        onClick={() => signOut({ callbackUrl: '/login' })}
+        variant="ghost"
+        size="sm"
+        className="p-1 h-auto"
+        title="Déconnexion"
+      >
+        <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 16l4-4m0 0l-4-4m4 4H7m6 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h4a3 3 0 013 3v1" />
+        </svg>
+      </Button>
+    </div>
+  )
+}

src/components/AuthProvider.tsx

@@ -0,0 +1,7 @@
+'use client'
+
+import { SessionProvider } from "next-auth/react"
+
+export function AuthProvider({ children }: { children: React.ReactNode }) {
+  return <SessionProvider>{children}</SessionProvider>
+}

src/components/TowerBackground.tsx

@@ -0,0 +1,11 @@
+export function TowerBackground() {
+  return (
+    <div className="absolute inset-0 bg-gradient-to-br from-[var(--primary)]/20 via-[var(--background)] to-[var(--accent)]/20">
+      {/* Effet de profondeur */}
+      <div className="absolute inset-0 bg-gradient-to-t from-black/20 via-transparent to-transparent"></div>
+      
+      {/* Effet de lumière */}
+      <div className="absolute inset-0 bg-gradient-to-br from-transparent via-[var(--primary)]/5 to-transparent"></div>
+    </div>
+  )
+}

src/components/TowerLogo.tsx

@@ -0,0 +1,37 @@
+interface TowerLogoProps {
+  size?: 'sm' | 'md' | 'lg'
+  showText?: boolean
+  className?: string
+}
+
+export function TowerLogo({ size = 'md', showText = true, className = '' }: TowerLogoProps) {
+  const sizeClasses = {
+    sm: 'w-12 h-12',
+    md: 'w-20 h-20',
+    lg: 'w-32 h-32'
+  }
+
+  const textSizes = {
+    sm: 'text-2xl',
+    md: 'text-4xl',
+    lg: 'text-6xl'
+  }
+
+  return (
+    <div className={`text-center ${className}`}>
+      <div className={`inline-flex items-center justify-center ${sizeClasses[size]} rounded-2xl mb-4 text-6xl`}>
+        🗼
+      </div>
+      {showText && (
+        <>
+          <h1 className={`${textSizes[size]} font-mono font-bold text-[var(--foreground)] mb-2`}>
+            TowerControl
+          </h1>
+          <p className="text-[var(--muted-foreground)] text-lg">
+            Tour de contrôle de vos projets
+          </p>
+        </>
+      )}
+    </div>
+  )
+}

src/components/ui/Header.tsx

@@ -8,6 +8,7 @@ import { useState } from 'react';
 import { Theme } from '@/lib/theme-config';
 import { THEME_CONFIG, getThemeMetadata } from '@/lib/theme-config';
 import { useKeyboardShortcutsModal } from '@/contexts/KeyboardShortcutsContext';
+import { AuthButton } from '@/components/AuthButton';
 
 interface HeaderProps {
   title?: string;
@@ -173,6 +174,12 @@ export function Header({ title = "TowerControl", subtitle = "Task Management", s
                 )}
               </button>
             </div>
+
+          </div>
+
+          {/* Auth controls à droite mobile */}
+          <div className="flex items-center gap-1">
+            <AuthButton />
           </div>
         </div>
 
@@ -264,9 +271,15 @@ export function Header({ title = "TowerControl", subtitle = "Task Management", s
                   </>
                 )}
               </div>
+
             </nav>
           </div>
 
+          {/* Contrôles à droite */}
+          <div className="flex items-center gap-2">
+            <AuthButton />
+          </div>
+
         </div>
 
       </div>