feat: complete Epic 0 — foundation migration & infrastructure setup

Stories 0.2-0.5: rename folders→declarations (backend+frontend), configure
Redis for cache/queue/sessions, add foundation database migrations
(permissions, archived_at), replace DeclarationStatus enum with architecture
lifecycle values, create DeclarationObserver for status transition validation
and auto-archive, fix controller status transitions to respect observer rules.

93 tests pass (240 assertions).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/Feature/Declaration/DeclarationStatusFlowTest.php

@@ -0,0 +1,108 @@
+<?php
+
+use App\Enums\DeclarationStatus;
+use App\Models\Declaration;
+use Illuminate\Validation\ValidationException;
+
+test('valid transition: created to en_cours', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+
+    expect($declaration->fresh()->status->value)->toBe('en_cours');
+});
+
+test('valid transition: en_cours to en_attente_client', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+
+    $declaration->update(['status' => DeclarationStatus::EnAttenteClient]);
+
+    expect($declaration->fresh()->status->value)->toBe('en_attente_client');
+});
+
+test('valid transition: en_attente_client to en_cours', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+    $declaration->update(['status' => DeclarationStatus::EnAttenteClient]);
+
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+
+    expect($declaration->fresh()->status->value)->toBe('en_cours');
+});
+
+test('valid transition: en_cours to termine', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+
+    $declaration->update(['status' => DeclarationStatus::Termine]);
+
+    expect($declaration->fresh()->status->value)->toBe('termine');
+});
+
+test('valid transition: termine to ferme', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+    $declaration->update(['status' => DeclarationStatus::Termine]);
+
+    $declaration->update(['status' => DeclarationStatus::Ferme]);
+
+    expect($declaration->fresh()->status->value)->toBe('ferme');
+});
+
+test('invalid transition: created to ferme throws validation exception', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+
+    $declaration->update(['status' => DeclarationStatus::Ferme]);
+})->throws(ValidationException::class);
+
+test('invalid transition: created to termine throws validation exception', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+
+    $declaration->update(['status' => DeclarationStatus::Termine]);
+})->throws(ValidationException::class);
+
+test('auto-archive: ferme status sets archived_at', function () {
+    $declaration = Declaration::factory()->create(['status' => DeclarationStatus::Created]);
+    $declaration->update(['status' => DeclarationStatus::EnCours]);
+    $declaration->update(['status' => DeclarationStatus::Termine]);
+
+    expect($declaration->fresh()->archived_at)->toBeNull();
+
+    $declaration->update(['status' => DeclarationStatus::Ferme]);
+
+    $fresh = $declaration->fresh();
+    expect($fresh->archived_at)->not->toBeNull();
+});
+
+test('scope active excludes archived declarations', function () {
+    $active = Declaration::factory()->create([
+        'status' => DeclarationStatus::Created,
+        'archived_at' => null,
+    ]);
+    $archived = Declaration::factory()->create([
+        'status' => DeclarationStatus::Created,
+        'archived_at' => now(),
+    ]);
+
+    $activeIds = Declaration::active()->pluck('id')->all();
+
+    expect($activeIds)->toContain($active->id);
+    expect($activeIds)->not->toContain($archived->id);
+});
+
+test('scope archived includes only archived declarations', function () {
+    $active = Declaration::factory()->create([
+        'status' => DeclarationStatus::Created,
+        'archived_at' => null,
+    ]);
+    $archived = Declaration::factory()->create([
+        'status' => DeclarationStatus::Created,
+        'archived_at' => now(),
+    ]);
+
+    $archivedIds = Declaration::archived()->pluck('id')->all();
+
+    expect($archivedIds)->toContain($archived->id);
+    expect($archivedIds)->not->toContain($active->id);
+});