feat: Reinitialize frontend with SvelteKit and TypeScript

- Delete old Vite+Svelte frontend
- Initialize new SvelteKit project with TypeScript
- Configure Tailwind CSS v4 + DaisyUI
- Implement JWT authentication with auto-refresh
- Create login page with form validation (Zod)
- Add protected route guards
- Update Docker configuration for single-stage build
- Add E2E tests with Playwright (6/11 passing)
- Fix Svelte 5 reactivity with $state() runes

Known issues:
- 5 E2E tests failing (timing/async issues)
- Token refresh implementation needs debugging
- Validation error display timing

backend/app/Models/User.php

@@ -0,0 +1,78 @@
+<?php
+
+namespace App\Models;
+
+// use Illuminate\Contracts\Auth\MustVerifyEmail;
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Foundation\Auth\User as Authenticatable;
+use Illuminate\Notifications\Notifiable;
+use Illuminate\Database\Eloquent\Concerns\HasUuids;
+use Tymon\JWTAuth\Contracts\JWTSubject;
+
+class User extends Authenticatable implements JWTSubject
+{
+    /** @use HasFactory<\Database\Factories\UserFactory> */
+    use HasFactory, Notifiable, HasUuids;
+
+    protected $primaryKey = 'id';
+    public $incrementing = false;
+    protected $keyType = 'string';
+
+    /**
+     * The attributes that are mass assignable.
+     *
+     * @var list<string>
+     */
+    protected $fillable = [
+        'name',
+        'email',
+        'password',
+        'role',
+    ];
+
+    /**
+     * The attributes that should be hidden for serialization.
+     *
+     * @var list<string>
+     */
+    protected $hidden = [
+        'password',
+        'remember_token',
+    ];
+
+    /**
+     * Get the attributes that should be cast.
+     *
+     * @return array<string, string>
+     */
+    protected function casts(): array
+    {
+        return [
+            'email_verified_at' => 'datetime',
+            'password' => 'hashed',
+        ];
+    }
+
+    /**
+     * Get the identifier that will be stored in the subject claim of the JWT.
+     *
+     * @return mixed
+     */
+    public function getJWTIdentifier()
+    {
+        return $this->getKey();
+    }
+
+    /**
+     * Return a key value array, containing any custom claims to be added to the JWT.
+     *
+     * @return array
+     */
+    public function getJWTCustomClaims()
+    {
+        return [
+            'role' => $this->role,
+            'email' => $this->email,
+        ];
+    }
+}