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/Artist.php

@@ -0,0 +1,107 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Models;
+
+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 Illuminate\Support\Str;
+use Spatie\Activitylog\Models\Concerns\LogsActivity;
+use Spatie\Activitylog\Support\LogOptions;
+
+final class Artist extends Model
+{
+    use HasFactory;
+    use HasUlids;
+    use LogsActivity;
+    use SoftDeletes;
+
+    protected static function booted(): void
+    {
+        self::addGlobalScope(new OrganisationScope);
+
+        self::creating(function (Artist $artist): void {
+            if (empty($artist->slug)) {
+                $artist->slug = $artist->generateUniqueSlug($artist->name);
+            }
+        });
+    }
+
+    protected $fillable = [
+        'organisation_id',
+        'name',
+        'slug',
+        'default_genre_id',
+        'default_draw',
+        'star_rating',
+        'home_base_country',
+        'agent_company_id',
+        'notes',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'default_draw' => 'integer',
+            'star_rating' => 'integer',
+        ];
+    }
+
+    public function getActivitylogOptions(): LogOptions
+    {
+        return LogOptions::defaults()
+            ->logFillable()
+            ->dontSubmitEmptyLogs();
+    }
+
+    private function generateUniqueSlug(string $name): string
+    {
+        $base = Str::slug($name);
+        $slug = $base;
+        $suffix = 2;
+
+        while (
+            self::withoutGlobalScope(OrganisationScope::class)
+                ->withTrashed()
+                ->where('organisation_id', $this->organisation_id)
+                ->where('slug', $slug)
+                ->exists()
+        ) {
+            $slug = "{$base}-{$suffix}";
+            $suffix++;
+        }
+
+        return $slug;
+    }
+
+    public function organisation(): BelongsTo
+    {
+        return $this->belongsTo(Organisation::class);
+    }
+
+    public function defaultGenre(): BelongsTo
+    {
+        return $this->belongsTo(Genre::class, 'default_genre_id');
+    }
+
+    public function agentCompany(): BelongsTo
+    {
+        return $this->belongsTo(Company::class, 'agent_company_id');
+    }
+
+    public function contacts(): HasMany
+    {
+        return $this->hasMany(ArtistContact::class);
+    }
+
+    public function engagements(): HasMany
+    {
+        return $this->hasMany(ArtistEngagement::class);
+    }
+}