fix: Corriger les tests E2E du dashboard admin après ajout des sections thématiques

Les tests attendaient 5 sections mais le dashboard en affiche 8
(5 thématiques + 3 placeholders DashboardSection). Le heading
sr-only "Actions de configuration" manquait pour l'accessibilité.

frontend/e2e/dashboard.spec.ts

@@ -380,12 +380,15 @@ test.describe('Dashboard', () => {
 			await switchToDemoRole(page, 'Admin');
 
 			const sectionTitles = page.locator('.dashboard-section .section-title');
-			await expect(sectionTitles).toHaveCount(5);
+			await expect(sectionTitles).toHaveCount(8);
 			await expect(sectionTitles.nth(0)).toHaveText('Personnes');
 			await expect(sectionTitles.nth(1)).toHaveText('Organisation');
 			await expect(sectionTitles.nth(2)).toHaveText('Année scolaire');
 			await expect(sectionTitles.nth(3)).toHaveText('Paramètres');
 			await expect(sectionTitles.nth(4)).toHaveText('Imports');
+			await expect(sectionTitles.nth(5)).toHaveText('Utilisateurs');
+			await expect(sectionTitles.nth(6)).toHaveText('Configuration');
+			await expect(sectionTitles.nth(7)).toHaveText('Activité récente');
 		});
 	});
 

frontend/src/lib/components/organisms/Dashboard/DashboardAdmin.svelte

@@ -75,6 +75,8 @@
 		{/if}
 	</header>
 
+	<h2 class="sr-only">Actions de configuration</h2>
+
 	{#each dashboardSections as section (section.id)}
 		<section class="dashboard-section" aria-labelledby="section-{section.id}">
 			<h2 id="section-{section.id}" class="section-title">{section.title}</h2>
@@ -141,6 +143,18 @@
 </div>
 
 <style>
+	.sr-only {
+		position: absolute;
+		width: 1px;
+		height: 1px;
+		padding: 0;
+		margin: -1px;
+		overflow: hidden;
+		clip: rect(0, 0, 0, 0);
+		white-space: nowrap;
+		border: 0;
+	}
+
 	.dashboard-admin {
 		display: flex;
 		flex-direction: column;