feat: fase 2 backend — crowd types, persons, sections, shifts, invite flow

- Crowd Types + Persons CRUD (73 tests)
- Festival Sections + Time Slots + Shifts CRUD met assign/claim flow (84 tests)
- Invite Flow + Member Management met InvitationService (109 tests)
- Schema v1.6 migraties volledig uitgevoerd
- DevSeeder bijgewerkt met crowd types voor testorganisatie

api/app/Http/Resources/Api/V1/ShiftResource.php

@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Http\Resources\Api\V1;
+
+use Illuminate\Http\Request;
+use Illuminate\Http\Resources\Json\JsonResource;
+
+final class ShiftResource extends JsonResource
+{
+    public function toArray(Request $request): array
+    {
+        return [
+            'id' => $this->id,
+            'festival_section_id' => $this->festival_section_id,
+            'time_slot_id' => $this->time_slot_id,
+            'location_id' => $this->location_id,
+            'title' => $this->title,
+            'description' => $this->description,
+            'instructions' => $this->instructions,
+            'coordinator_notes' => $this->when(
+                $this->shouldShowCoordinatorNotes($request),
+                $this->coordinator_notes,
+            ),
+            'slots_total' => $this->slots_total,
+            'slots_open_for_claiming' => $this->slots_open_for_claiming,
+            'is_lead_role' => $this->is_lead_role,
+            'report_time' => $this->report_time,
+            'actual_start_time' => $this->actual_start_time,
+            'actual_end_time' => $this->actual_end_time,
+            'allow_overlap' => $this->allow_overlap,
+            'status' => $this->status,
+            'filled_slots' => $this->filled_slots,
+            'fill_rate' => $this->fill_rate,
+            'effective_start_time' => $this->effective_start_time,
+            'effective_end_time' => $this->effective_end_time,
+            'created_at' => $this->created_at->toIso8601String(),
+            'time_slot' => new TimeSlotResource($this->whenLoaded('timeSlot')),
+            'location' => new LocationResource($this->whenLoaded('location')),
+            'festival_section' => new FestivalSectionResource($this->whenLoaded('festivalSection')),
+        ];
+    }
+
+    private function shouldShowCoordinatorNotes(Request $request): bool
+    {
+        $user = $request->user();
+        if (! $user) {
+            return false;
+        }
+
+        if ($user->hasRole('super_admin')) {
+            return true;
+        }
+
+        $shift = $this->resource;
+        $event = $shift->festivalSection?->event;
+        if (! $event) {
+            return false;
+        }
+
+        return $event->organisation->users()
+            ->where('user_id', $user->id)
+            ->wherePivot('role', 'org_admin')
+            ->exists()
+            || $event->users()
+                ->where('user_id', $user->id)
+                ->wherePivot('role', 'event_manager')
+                ->exists();
+    }
+}