🗃️ Add database schema, models & seeders (Story 1.2)

Migrations (translations, projects, skills, skill_project), Eloquent models
with belongsToMany relations, scopes, and test seeders (74 translations FR/EN,
10 skills, 3 projects, 12 skill-project links).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

api/database/seeders/DatabaseSeeder.php

@@ -2,7 +2,6 @@
 
 namespace Database\Seeders;
 
-use App\Models\User;
 use Illuminate\Database\Console\Seeds\WithoutModelEvents;
 use Illuminate\Database\Seeder;
 
@@ -10,16 +9,13 @@ class DatabaseSeeder extends Seeder
 {
     use WithoutModelEvents;
 
-    /**
-     * Seed the application's database.
-     */
     public function run(): void
     {
-        // User::factory(10)->create();
-
-        User::factory()->create([
-            'name' => 'Test User',
-            'email' => 'test@example.com',
+        $this->call([
+            TranslationSeeder::class,
+            SkillSeeder::class,
+            ProjectSeeder::class,
+            SkillProjectSeeder::class,
         ]);
     }
 }