feat: consolidate frontend API layer, add query-client, and harden backend Fase 1

Frontend:
- Consolidate duplicate API layers into single src/lib/axios.ts per app
- Remove src/lib/api-client.ts and src/utils/api.ts (admin)
- Add src/lib/query-client.ts with TanStack Query config per app
- Update all imports and auto-import config

Backend:
- Fix organisations.billing_status default to 'trial'
- Fix user_invitations.invited_by_user_id to nullOnDelete
- Add MeResource with separated app_roles and pivot-based org roles
- Add cross-org check to EventPolicy view() and update()
- Restrict EventPolicy create/update to org_admin/event_manager (not org_member)
- Attach creator as org_admin on organisation store
- Add query scopes to Event and UserInvitation models
- Improve factories with Dutch test data
- Expand test suite from 29 to 41 tests (90 assertions)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/app/Models/UserInvitation.php

@@ -4,6 +4,7 @@ declare(strict_types=1);
 
 namespace App\Models;
 
+use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Concerns\HasUlids;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
@@ -46,4 +47,15 @@ final class UserInvitation extends Model
     {
         return $this->belongsTo(Event::class);
     }
+
+    public function scopePending(Builder $query): Builder
+    {
+        return $query->where('status', 'pending');
+    }
+
+    public function scopeExpired(Builder $query): Builder
+    {
+        return $query->where('status', 'expired')
+            ->orWhere(fn (Builder $q) => $q->where('status', 'pending')->where('expires_at', '<', now()));
+    }
 }