feat: Provisionner automatiquement un nouvel établissement

Lorsqu'un super-admin crée un établissement via l'interface, le système
doit automatiquement créer la base tenant, exécuter les migrations,
créer le premier utilisateur admin et envoyer l'invitation — le tout
de manière asynchrone pour ne pas bloquer la réponse HTTP.

Ce mécanisme rend chaque établissement opérationnel dès sa création
sans intervention manuelle sur l'infrastructure.

frontend/tests/unit/lib/features/grades/stores/gradePreferences.test.ts

@@ -0,0 +1,172 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+// Mock $app/environment
+vi.mock('$app/environment', () => ({
+	browser: true
+}));
+
+describe('gradePreferences', () => {
+	beforeEach(() => {
+		localStorage.clear();
+		vi.resetModules();
+	});
+
+	async function loadModule() {
+		return await import('$lib/features/grades/stores/gradePreferences.svelte');
+	}
+
+	// ==========================================================================
+	// Reveal mode (discover vs immediate)
+	// ==========================================================================
+	describe('reveal mode', () => {
+		it('defaults to immediate mode', async () => {
+			const prefs = await loadModule();
+			expect(prefs.getRevealMode()).toBe('immediate');
+			expect(prefs.isDiscoverMode()).toBe(false);
+		});
+
+		it('switches to discover mode', async () => {
+			const prefs = await loadModule();
+			prefs.setRevealMode('discover');
+
+			expect(prefs.getRevealMode()).toBe('discover');
+			expect(prefs.isDiscoverMode()).toBe(true);
+		});
+
+		it('switches back to immediate mode', async () => {
+			const prefs = await loadModule();
+			prefs.setRevealMode('discover');
+			prefs.setRevealMode('immediate');
+
+			expect(prefs.getRevealMode()).toBe('immediate');
+			expect(prefs.isDiscoverMode()).toBe(false);
+		});
+
+		it('persists reveal mode to localStorage', async () => {
+			const prefs = await loadModule();
+			prefs.setRevealMode('discover');
+
+			const stored = JSON.parse(localStorage.getItem('classeo_grade_preferences')!);
+			expect(stored.revealMode).toBe('discover');
+		});
+
+		it('restores reveal mode from localStorage on init', async () => {
+			localStorage.setItem(
+				'classeo_grade_preferences',
+				JSON.stringify({ revealMode: 'discover' })
+			);
+
+			const prefs = await loadModule();
+			expect(prefs.getRevealMode()).toBe('discover');
+			expect(prefs.isDiscoverMode()).toBe(true);
+		});
+
+		it('handles corrupted localStorage gracefully', async () => {
+			localStorage.setItem('classeo_grade_preferences', 'not-json');
+
+			const prefs = await loadModule();
+			expect(prefs.getRevealMode()).toBe('immediate');
+		});
+	});
+
+	// ==========================================================================
+	// Grade reveal state (per-grade reveal tracking)
+	// ==========================================================================
+	describe('grade reveal state', () => {
+		it('reports grades as not revealed by default', async () => {
+			const prefs = await loadModule();
+			expect(prefs.isGradeRevealed('grade-1')).toBe(false);
+		});
+
+		it('reveals a grade individually', async () => {
+			const prefs = await loadModule();
+			prefs.revealGrade('grade-1');
+
+			expect(prefs.isGradeRevealed('grade-1')).toBe(true);
+			expect(prefs.isGradeRevealed('grade-2')).toBe(false);
+		});
+
+		it('persists revealed grades to localStorage', async () => {
+			const prefs = await loadModule();
+			prefs.revealGrade('grade-1');
+			prefs.revealGrade('grade-2');
+
+			const stored = JSON.parse(localStorage.getItem('classeo_grades_revealed')!);
+			expect(stored).toContain('grade-1');
+			expect(stored).toContain('grade-2');
+		});
+
+		it('restores revealed grades from localStorage on init', async () => {
+			localStorage.setItem(
+				'classeo_grades_revealed',
+				JSON.stringify(['grade-1', 'grade-3'])
+			);
+
+			const prefs = await loadModule();
+			expect(prefs.isGradeRevealed('grade-1')).toBe(true);
+			expect(prefs.isGradeRevealed('grade-3')).toBe(true);
+			expect(prefs.isGradeRevealed('grade-2')).toBe(false);
+		});
+
+		it('handles corrupted revealed localStorage gracefully', async () => {
+			localStorage.setItem('classeo_grades_revealed', '{invalid}');
+
+			const prefs = await loadModule();
+			expect(prefs.isGradeRevealed('grade-1')).toBe(false);
+		});
+	});
+
+	// ==========================================================================
+	// Grade "new" badge (seen tracking)
+	// ==========================================================================
+	describe('grade new badge', () => {
+		it('reports unseen grades as new', async () => {
+			const prefs = await loadModule();
+			expect(prefs.isGradeNew('grade-1')).toBe(true);
+		});
+
+		it('marks grades as seen', async () => {
+			const prefs = await loadModule();
+			prefs.markGradesSeen(['grade-1', 'grade-2']);
+
+			expect(prefs.isGradeNew('grade-1')).toBe(false);
+			expect(prefs.isGradeNew('grade-2')).toBe(false);
+			expect(prefs.isGradeNew('grade-3')).toBe(true);
+		});
+
+		it('persists seen grades to localStorage', async () => {
+			const prefs = await loadModule();
+			prefs.markGradesSeen(['grade-1']);
+
+			const stored = JSON.parse(localStorage.getItem('classeo_grades_seen')!);
+			expect(stored).toContain('grade-1');
+		});
+
+		it('restores seen grades from localStorage on init', async () => {
+			localStorage.setItem(
+				'classeo_grades_seen',
+				JSON.stringify(['grade-1'])
+			);
+
+			const prefs = await loadModule();
+			expect(prefs.isGradeNew('grade-1')).toBe(false);
+			expect(prefs.isGradeNew('grade-2')).toBe(true);
+		});
+
+		it('accumulates seen grades across multiple calls', async () => {
+			const prefs = await loadModule();
+			prefs.markGradesSeen(['grade-1']);
+			prefs.markGradesSeen(['grade-2']);
+
+			expect(prefs.isGradeNew('grade-1')).toBe(false);
+			expect(prefs.isGradeNew('grade-2')).toBe(false);
+		});
+
+		it('handles corrupted seen localStorage gracefully', async () => {
+			localStorage.setItem('classeo_grades_seen', 'broken');
+
+			const prefs = await loadModule();
+			expect(prefs.isGradeNew('grade-1')).toBe(true);
+		});
+	});
+});