Add sharing options and a printable flyer page to the website

Implement share and PDF export buttons on the home page, and create a new flyer page with a customizable QR code for printing and distribution.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 923ae0e3-a363-4db8-b04a-e8baca2a1330
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Event-Id: a2b8df7d-660f-4020-961b-e37cb231d6a4
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/8af7d2ec-2cc3-4ece-8af3-9f071488d072/923ae0e3-a363-4db8-b04a-e8baca2a1330/Z3YUti7
Replit-Helium-Checkpoint-Created: true

artifacts/voix-du-peuple/src/App.tsx

@@ -6,6 +6,7 @@ import NotFound from "@/pages/not-found";
 import Home from "@/pages/home";
 import About from "@/pages/about";
 import Transparence from "@/pages/transparence";
+import Flyer from "@/pages/flyer";
 
 const queryClient = new QueryClient({
   defaultOptions: {
@@ -27,6 +28,7 @@ function Navbar() {
           <Link href="/" className="transition-colors hover:text-foreground/80 text-foreground/60" data-testid="nav-manifesto-link">Manifeste</Link>
           <Link href="/about" className="transition-colors hover:text-foreground/80 text-foreground/60" data-testid="nav-about-link">À propos</Link>
           <Link href="/transparence" className="transition-colors hover:text-foreground/80 text-foreground/60" data-testid="nav-transparence-link">Fonctionnement</Link>
+          <Link href="/flyer" className="transition-colors hover:text-foreground/80 text-foreground/60" data-testid="nav-flyer-link">Flyer QR</Link>
         </nav>
         <div className="ml-auto flex items-center">
           <span
@@ -54,6 +56,7 @@ function Router() {
           <Route path="/" component={Home} />
           <Route path="/about" component={About} />
           <Route path="/transparence" component={Transparence} />
+          <Route path="/flyer" component={Flyer} />
           <Route component={NotFound} />
         </Switch>
       </main>