feat(timetable): Artist domain — 7 enums + 9 Eloquent models

Enums under App\Enums\Artist\ (PascalCase per FormBuilder convention,
snake_case wire values per RFC):
- ArtistEngagementStatus (D9, 9 states + Dutch labels)
- BumaHandledBy (D26)
- FeeType, PaymentStatus
- AdvanceSectionType, AdvanceSectionSubmissionStatus, AdvanceSubmissionStatus

Models:
- Artist (org-scoped, slug-unique-per-org via creating boot hook)
- ArtistEngagement (per-event booking, denorm organisation_id)
- Genre, Stage (event-scoped, ordered scope), StageDay (Pivot, int PK)
- Performance (engagement-scoped, isParked() helper)
- AdvanceSection, AdvanceSubmission, ArtistContact (primary scope)

OrganisationScope wired:
- Direct organisation_id: Artist, Genre, ArtistEngagement
- FK-chain via tenantScopeStrategy(): Stage→Event, Performance→Engagement,
  AdvanceSection→Engagement, AdvanceSubmission→Section→Engagement,
  ArtistContact→Artist, StageDay→Stage→Event

Soft-deletes: Artist, ArtistEngagement, Performance (per RFC §5.4).
LogsActivity baseline (logFillable+dontSubmitEmptyLogs) on all business
models — actual mutation surfaces wire LogOptions in Session 2+.

Inverse relations added on Organisation, Event, Company.
companies.handles_buma cast added.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

api/app/Models/ArtistEngagement.php

@@ -0,0 +1,123 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Models;
+
+use App\Enums\Artist\ArtistEngagementStatus;
+use App\Enums\Artist\BumaHandledBy;
+use App\Enums\Artist\FeeType;
+use App\Enums\Artist\PaymentStatus;
+use App\Models\Scopes\OrganisationScope;
+use Illuminate\Database\Eloquent\Concerns\HasUlids;
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+use Illuminate\Database\Eloquent\SoftDeletes;
+use Spatie\Activitylog\Models\Concerns\LogsActivity;
+use Spatie\Activitylog\Support\LogOptions;
+
+final class ArtistEngagement extends Model
+{
+    use HasFactory;
+    use HasUlids;
+    use LogsActivity;
+    use SoftDeletes;
+
+    protected static function booted(): void
+    {
+        self::addGlobalScope(new OrganisationScope);
+    }
+
+    protected $fillable = [
+        'organisation_id',
+        'artist_id',
+        'event_id',
+        'booking_status',
+        'project_leader_id',
+        'fee_amount',
+        'fee_currency',
+        'fee_type',
+        'buma_applicable',
+        'buma_percentage',
+        'buma_handled_by',
+        'vat_applicable',
+        'vat_percentage',
+        'deal_breakdown',
+        'deposit_percentage',
+        'deposit_due_date',
+        'balance_due_date',
+        'payment_status',
+        'crew_count',
+        'guests_count',
+        'requested_at',
+        'option_expires_at',
+        'advance_open_from',
+        'advance_open_to',
+        'portal_token',
+        'advancing_completed_count',
+        'advancing_total_count',
+        'notes',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'booking_status' => ArtistEngagementStatus::class,
+            'fee_type' => FeeType::class,
+            'buma_handled_by' => BumaHandledBy::class,
+            'payment_status' => PaymentStatus::class,
+            'buma_applicable' => 'boolean',
+            'vat_applicable' => 'boolean',
+            'deal_breakdown' => 'array',
+            'deposit_due_date' => 'date',
+            'balance_due_date' => 'date',
+            'crew_count' => 'integer',
+            'guests_count' => 'integer',
+            'requested_at' => 'datetime',
+            'option_expires_at' => 'datetime',
+            'advance_open_from' => 'datetime',
+            'advance_open_to' => 'datetime',
+            'advancing_completed_count' => 'integer',
+            'advancing_total_count' => 'integer',
+        ];
+    }
+
+    public function getActivitylogOptions(): LogOptions
+    {
+        return LogOptions::defaults()
+            ->logFillable()
+            ->dontSubmitEmptyLogs();
+    }
+
+    public function organisation(): BelongsTo
+    {
+        return $this->belongsTo(Organisation::class);
+    }
+
+    public function artist(): BelongsTo
+    {
+        return $this->belongsTo(Artist::class);
+    }
+
+    public function event(): BelongsTo
+    {
+        return $this->belongsTo(Event::class);
+    }
+
+    public function projectLeader(): BelongsTo
+    {
+        return $this->belongsTo(User::class, 'project_leader_id');
+    }
+
+    public function performances(): HasMany
+    {
+        return $this->hasMany(Performance::class, 'engagement_id');
+    }
+
+    public function advanceSections(): HasMany
+    {
+        return $this->hasMany(AdvanceSection::class, 'engagement_id');
+    }
+}