feat: implement Story 2.1 — Owner/Manager Command Center Dashboard

- Rewrite DashboardController with cached role-scoped KPI aggregation
  (Cache::remember, 5-min TTL, Declaration::forUser scope)
- Create StatCard.vue component with CVA status variants and a11y
- Rewrite Dashboard.vue with 4-column KPI grid + urgent declarations table
- Add mise_en_demeure status to DeclarationStatus enum with transitions
- Exclude termine, mise_en_demeure, ferme from dashboard queries
- Set deadline proximity red threshold to ≤5 days
- Add abort(404) for non-member workspace access per architecture
- Fix null-safe client access for soft-deleted clients
- Fix hardcoded routes with Wayfinder type-safe imports
- Fix DashboardProps.stats type to allow null
- Add aria-pressed to StatCard for accessibility
- Install shadcn-vue table component (11 files)
- Add 11 Pest feature tests + 3 mise_en_demeure transition tests
- Fix DeclarationFactory eager workspace creation causing slug collisions
- 196 tests pass, 836 assertions, zero regressions

database/factories/WorkspaceFactory.php

@@ -17,7 +17,7 @@ class WorkspaceFactory extends Factory
      */
     public function definition(): array
     {
-        $name = fake()->company();
+        $name = fake()->unique()->company();
         $slug = Str::slug($name);
 
         return [